STS-125/HST SM-4 MISSION ARCHIVE (FINAL)
Updated through: 05/27/09

By William Harwood
CBS News/Kennedy Space Center

The following copy originally was posted on the Current Mission space page at http://cbsnews.com/network/news/space/current.html.

Comments, suggestions and corrections welcome!

TABLE OF CONTENTS


1:15 PM, 5/24/09, Update: Shuttle Atlantis lands in California (UPDATED with quotes and details from post-landing news conference)

Delayed two days by stormy Florida weather, the shuttle Atlantis glided to a California landing today, closing out a successful mission to overhaul the Hubble Space Telescope with a picture-perfect Mojave Desert touchdown.

With commander Scott Altman and pilot Gregory C. Johnson at the controls, Atlantis crossed the coast of California northwest of Los Angeles on a steep descent to Edwards Air Force Base, rattling the countryside with twin sonic booms.

Taking over manual control at an altitude of about 50,000 feet, Altman guided the shuttle through a sweeping 200-degree left-overhead turn to line up on runway 22 at the fabled Air Force test center.

As Altman flared the shuttle's descent and pulled its nose up slightly on final approach, Johnson lowered the landing gear and Atlantis settled to a smooth touchdown at 11:39:05 a.m. EDT to close out NASA's final mission to Hubble.

Space shuttle Atlantis on final at Edwards Air Force Base (Photo: NASA TV)

"Houston, Atlantis, wheels stopped, Edwards, 22!" Altman radioed mission control at the Johnson Space Center as Atlantis rolled to a halt.

"Welcome home, Atlantis," astronaut Gregory H. Johnson replied from Houston. "Congratulations on a very successful mission, giving Hubble a new set of eyes that will continue to expand our knowledge of the universe."

"Thank you, Houston, it was a thrill from start to finish," Altman said. "We've had a great ride. It took a whole team across the country to pull it off. Our hats are off to you all. Thank you so much."

Mission duration was 12 days 21 hours 37 minutes and nine seconds for a flight covering 5.2 million miles and 197 complete orbits since blastoff May 11 from Florida's Kennedy Space Center.

"I didn't realize it was going to be so hard to get back to the Earth!" Altman said after a brief walk-around inspection of the shuttle. "We're all thrilled to have the mission complete."

Altman, Johnson, flight engineer Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good planned to fly back to Houston late today or early Monday for reunions with family and friends.

"Now and only now can we declare this mission a total success," said Ed Weiler, NASA's associate administrator for space science. "We've now entered the second chapter of the great American comeback story.

"This mission ... was canceled Jan. 16, 2004," he said, referring to post-Columbia safety concerns. "If you'd have told me on that day I'd be sitting here five years later with a totally successful five-EVA mission, with a brand new Hubble once again that will probably operate well into the third decade of its life, I wouldn't have bet you a penny. But Hubble is the great American comback story, chapter two."

Weiler said engineers at the Goddard Space Flight Center's Space Telescope Operations Control Center are in the process of testing Hubble's new instruments and subsystems and "everything is going very smoothly, no problems so far."

Landing in California will add a week to 10 days to Atlantis' processing for its next mission in November and cost NASA about $1.8 million. It also will delay access to an electronics box that failed at launch May 11. Engineers want to make sure a short circuit affecting the aerosurface actuator in question will not affect any systems aboard the shuttle Endeavour, scheduled for launch June 13.

Mike Moses, director of shuttle integration at the Kennedy Space Center, said he is confident the issue will be resolved in time for Endeavour's flight. Likewise, launch Director Mike Leinbach said Atlantis' diversion to Edwards will have no direct impact on Endeavour's processing.

Because Endeavour was on hot standby for launch on an emergency rescue mission in case the Atlantis astronauts ran into any major problems, much of its launch processing is already complete.

"One of the key things we did in the processing meetings was make sure we had a sufficient work force to go out to California, process Atlantis and get her ready to come home in addition to processing Endeavour here," he said. "When you think about it, there's not much left to do on Endeavour."

Engineers plan to move Endeavour from launch pad 39B to pad 39A next Friday. A flight readiness review is on tap June 3.

"A lot of the work on Endeavour's already done, we've got a good head start on that," Leinbach said. "Without a doubt, we have sufficient people to process them, make that 13th launch date. It's just not an issue for us."

Altman and company had hoped to close out the 126th shuttle mission Friday with a landing at the Kennedy Space Center. But low clouds and thundershowers at the Florida spaceport forced entry Flight Director Norm Knight to order a waveoff in hopes of better conditions Saturday.

The astronauts ran into more of the same Saturday. Knight considered diverting the crew to Edwards then, but ended up deciding the wave off another day in hopes of better weather Sunday. Atlantis had enough on-board supplies to remain in orbit through Monday and forecasters were predicting slightly better conditions in Florida for the crew's third attempt.

Conditions were, in fact, better but with offshore clouds and rain threatening to move into the landing zone, Knight ordered another waveoff and diverted the crew to Edwards to close out a high-stakes mission that left the Hubble Space Telescope in its best health since launch in 1990.

Over the course of five back-to-back spacewalks, the Atlantis astronauts installed two new instruments, repaired two others, replaced the observatory's six batteries and stabilizing gyroscopes, installed a new star sensor, a replacement science computer and three insulation panels.

Engineers at the Space Telescope Operations Control Center say it will take weeks to calibrate and test the new instruments and return Hubble to normal service. The first images from the refurbished telescope are expected in early September.

"Hubble has been a roller coaster ride going all the way back to the '80s," Weiler told CBS News. "It's mighty sweet to see (Atlantis' mission) happen, it's even sweeter to see it happen successfully."

The upgrades should permit Hubble to operate an additional five years, and possible 10, Weiler said.

"We've got new gyros, new instruments, old instruments that were dead and are now alive, what more could you ask for?" he said. "It's sad to know this is the end of an era. It's not the end of Hubble, it's the beginning of the new Hubble. But it's the last time we'll be servicing the Hubble with (the shuttle). And that's sad.

"But on the other hand, we've had a good ride. It was supposed to be a 10- to 15-year mission. We're in our 19th year, we may get 29 years. That's not a bad return on investment."

Atlantis' landing kicks off a busy few weeks for NASA. On Wednesday, at 6:34 a.m. EDT, the Russians plan to launch the Soyuz TMA-14 spacecraft from the Baikonur Cosmodrome carrying three additional astronauts and cosmonauts to the International Space Station, boosting the lab's crew to six for the first time.

Expedition 19 commander Gennady Padalka, flight engineer Michael Barratt, a NASA physician-astronaut, and Japanese astronaut Koichi Wakata will be joined by Roman Romanenko, a second-generation cosmonaut, European Space Agency astronaut Frank De Winne of Belgium and Canadian Space Agency astronaut Robert Thirsk.

At the Kennedy Space Center, meanwhile, engineers plan to follow the Soyuz launch with Endeavour's takeoff on a five-spacewalk assembly mission. Because of temperature constraints related to the station's orbit, NASA will only have one week to get Endeavour off the ground or the flight will be delayed to mid July.


10:05 AM, 5/24/09, Update: Atlantis diverted to Edwards Air Force Base

At 10:02 a.m., astronaut Gregory H. Johnson in mission control at the Johnson Space Center told the Atlantis astronauts to pass up a second and final chance to land at the Kennedy Space Center today and instead the prepare for a deorbit rocket firing at 10:24:41 a.m. Landing at Edwards Air Force Base in California's Mojave Desert is expected around 11:39 a.m. EDT.

Weather at the Kennedy Space Center was marginal today and while flight controllers initially held out hope of getting Atlantis home to Florida, entry Flight Director Norm Knight decided conditions were too unstable to reliably predict, and the crew was ordered to Edwards. The weather in California is ideal, with clear skies and light winds.


8:30 AM, 5/24/09, Update: Atlantis landing delayed one orbit

Despite better weather today in Florida, conditions were too unstable to reliably predict and entry Flight Director Norm Knight decided to delay the shuttle Atlantis return to Earth by one more orbit, setting the stage for a landing in either Florida or California.

"We are going to wave off this rev," astronaut Gregory H. Johnson radioed from mission control. "The weather is looking good at KSC, but not good enough for us to get comfortable. The atmosphere is unstable. As the temperature rises, it's going to approach the trigger point to trigger off thunderstorms. You've got a forecast of thunderstorms within 30 (nautical miles) and so we are going to target KSC and Edwards, we're going to keep both options open for the next rev."

"OK, Houston, we copy, we're waving off this rev. Thanks," commander Scott Altman called down from orbit.

The astronauts have an opportunity to land at Edwards Air Force Base, Calif., on the next orbit, at 11:38 a.m. EDT, and an opportunity to land at Kennedy, at 11:48 a.m. A decision must be made before the deorbit rocket firing to Edwards, targeted for 10:24 a.m.


7:45 AM, 5/24/09, Update: Florida weather better, but still uncertain

The weather is better today at the Kennedy Space Center as the shuttle Atlantis' first Florida landing opportunity approaches. A low deck of broken clouds has not yet materialized over the shuttle runway, but it's not yet clear whether off-shore clouds and showers will move on shore as predicted.

NASA flight rules forbid an entry attempt if rain is seen within 30 nautical miles of the runway and that is clearly an issue. The weather at NASA's backup landing site at Edwards Air Force Base, Calif., is ideal.

To make the first Florida landing opportunity, commander Scott Altman and pilot Gregory C. Johnson must fire Atlantis' twin orbital maneuvering system braking rockets for two minutes and 29 seconds starting at 8:57:06 a.m. That would set up a touchdown on runway 33 around 10:09:28 a.m.

If the weather doesn't cooperate, or if conditions are too dynamic to reliably predict, entry Flight Director Norm Knight will wave off the first landing attempt and send the crew around the planet again. Two landing opportunities will be available at that point, one at Edwards at 11:389 a.m. and the other at Kennedy at 11:48 a.m.


5:30 AM, 5/24/09, Update: Astronauts ready shuttle for third landing try

Delayed two days by stormy weather in Florida, the Atlantis astronauts rigged the shuttle for re-entry again today, prepared to head for California if necessary to finally close out their Hubble Space Telescope repair mission.

The crew has two opportunities to land at Florida's Kennedy Space Center today, the first at 10:09 a.m. and the second at 11:48 a.m., and two at Edwards Air Force Base, Calif., one at 11:38 a.m. EDT and the other at 1:17 p.m. EDT.

The astronauts were awakened shortly after 1 a.m. by a recording of Richard Wagner's "Ride of the Valkyries" beamed up from mission control by the overnight planning shift.

"And Houston, we want to take a minute before you guys go off shift to say thank you for staying with us through this weekend," commander Scott Altman said later. "I know it's meant a lot of folks spent the weekend in MCC (mission control center) instead of at the beach for the Memorial Day weekend. We appreciate the sacrifices that are being made to support us while we're continuing to go around. We surely do appreciate it."

The Spaceflight Meteorology Group at the Johnson Space Center in Houston is predicting a chance of thundershowers within 30 nautical miles of the Kennedy Space Center runway and a deck of broken clouds at 3,500 feet, both violations of NASA's entry flight rules. The forecast for Edwards Air Force Base in California's Mojave Desert calls for clear skies and light winds.

"We're marching into deorbit prep," astronaut Gregory H. Johnson radioed from mission control just before 5 a.m. "We've gotten an initial weather brief on KSC. It's a similar pattern to yesterday. We are going to march down just like we did yesterday to (payload bay) door closure (around 6:15 a.m.) and see where we get. We're also closely watching Edwards, orbit 197, that's the first opportunity into Edwards. So (we're) looking at KSC for the first rev and then your second orbit, we'll be looking at KSC and Edwards."

"OK, Houston," Altman replied. "That's kind of what I expected. Basically, look at the first orbit to KSC and then make a call on the second orbit for Edwards or KSC."

"Yes, and to wrap that up with a bow, Scooter, the weather at Edwards is looking great," Johnson said.

"OK, that's nice to know, that Edwards is solid as a backup."

"Roger, the sky is clear out there in California and the wind is right down the runway at about 17 knots."

"Sounds good," Altman said.

The astronauts originally hoped to land Friday, but low clouds and thundershowers from a low pressure system forced entry Flight Director Norm Knight to order a one-day wave off. Conditions were roughly the same Saturday and Knight considered diverting the crew to California. But in the end, despite a marginal forecast, he decided on another one-day wave off in hopes of better conditions today.

A landing in California would cost NASA's about $1.8 million and a week to 10 days of lost processing time. But another concern is getting access to an avionics box in the orbiter's engine compartment that failed right at liftoff May 11.

The aerosurface actuator control box is one of four redundant units used to format computer commands to the hydraulic actuators that move the shuttle's elevons and rudder/speedbrake. The failure in ASA-1 caused no problems for Atlantis, but NASA managers need to make sure it's not the result of some generic problem that could affect the shuttle Endeavour, scheduled for launch June 13.

If Atlantis is diverted to California, access to the failed unit will be delayed and engineers will not have as much time for troubleshooting. Endeavour's flight readiness review is planned for June 3.


7:10 PM, 5/23/09, Update: Deorbit timelines for Sunday (UPDATED at 3:20 a.m. with corrected times for rev 197 deorbit to KSC; corrected entry interface time for rev 196 deorbit to KSC)

Flight controllers at the Johnson Space Center in Houston have updated the shuttle Atlantis' deorbit and landing times for Sunday. The astronauts will have two landing opportunities at the Kennedy Space Center in Florida, the first coming at 10:09:28 a.m., and two at Edwards Air Force Base, Calif. Here are updated entry timelines for all four opportunities (in EDT; best viewed with fixed-width font):

EDT...........EVENT

Rev. 196 Deorbit to KSC

Deorbit ignition (TIG): 08:56:56 AM (dV: 171 mph; dT: 02:31)
Crossrange: 173 statute miles
Range to KSC at entry interface: 4,909 statute miles
Landing: 10:09:28 AM

04:56 AM......Begin deorbit timeline
05:11 AM......Radiator stow
05:21 AM......Mission specialists seat installation
05:27 AM......Computers set for deorbit prep
05:31 AM......Hydraulic system configuration
05:56 AM......Flash evaporator checkout
06:02 AM......Final payload deactivation
06:16 AM......Payload bay doors closed
06:26 AM......Mission control 'go' for OPS-3 software load
06:36 AM......OPS-3 entry software loaded
07:01 AM......Entry switchlist verification
07:11 AM......Deorbit maneuver update
07:16 AM......Crew entry review
07:31 AM......CDR/PLT don entry suits
07:48 AM......IMU alignment
07:56 AM......CDR/PLT strap in; MS suit don
08:13 AM......Shuttle steering check
08:16 AM......Hydraulic system prestart
08:23 AM......Toilet deactivation
08:36 AM......MCC 'go' for deorbit burn
08:42 AM......MS seat ingress
08:51 AM......Single APU start

08:56:56 AM...Deorbit ignition
08:59:27 AM...Deorbit burn complete

09:38:12 AM...Entry interface
09:42:39 AM...1st roll command to left
09:51:06 AM...1st right-to-let roll reversal
09:56:28 AM...C-band radar acquisition
10:03:02 AM...Velocity less than mach 2.5
10:05:12 AM...Velocity less than mach 1
10:05:28 AM...305-degree left turn to runway 15
10:09:28 AM...Landing

-----------------------------------------------

Rev. 197 Deorbit to EDW

TIG: 10:24:06 AM (dV: 182 mph; dT: 2:40)
Crossrange: 467 sm
Range to EDW at entry interface: 4,889 sm
Landing: 11:38:52 AM

10:04 AM......MCC 'go' for deorbit burn
10:10 AM......MS seat ingress
10:19 AM......Single APU start

10:24:06 AM...Deorbit ignition
10:26:46 AM...Deorbit burn complete

11:07:54 AM...Entry interface
11:12:23 AM...1st roll command to left
11:23:41 AM...1st left-to-right roll reversal
11:32:38 AM...Velocity less than mach 2.5
11:34:51 AM...Velocity less than mach 1
11:35:45 AM...205-degree left turn to runway 22
11:38:52 AM...Landing

-----------------------------------------------

Rev. 197 Deorbit to KSC

TIG: 10:40:56 AM (dV: 171 mph; dT: 2:32)
Crossrange: 632 sm
Range to KSC at entry interface: 4,878 sm
Landing: 11:48:16 AM

10:20 AM......MCC 'go' for deorbit burn
10:26 AM......MS seat ingress
10:35 AM......Single APU start

10:40:56 AM...Deorbit ignition
10:43:28 AM...Deorbit burn complete

11:17:07 AM...Entry interface
11:21:34 AM...1st roll command to left
11:34:26 AM...1st left-to-right roll reversal
11:41:53 AM...Velocity less than mach 2.5
11:44:02 AM...Velocity less than mach 1
11:44:16 AM...304 degree left turn to runway 15
11:48:16 AM...Landing

-----------------------------------------------

Rev. 198 Deorbit to EDW

TIG: 12:07:06 PM (dV: 168 mph; dT: 2:28)
Crossrange: 754 sm
Range to EDW at entry interface: 4,864 sm
Landing: 01:17:43 PM

11:47 AM......MCC 'go' for deorbit burn
11:53 AM......MS seat ingress
12:02 PM......Single APU start

12:07:06 PM...Deorbit ignition
12:09:35 PM...Deorbit burn complete

12:46:40 PM...Entry interface
12:51:06 PM...1st roll command to left
01:05:23 PM...1st left-to-right roll reversal
01:11:31 PM...Velocity less than mach 2.5
01:13:43 PM...Velocity less than mach 1
01:14:38 PM...200-degree left turn to runway 22
01:17:43 PM...Landing


08:55 AM, 5/23/09, Update: WAVEOFF - Atlantis crew told to delay landing to Sunday; Bolden nominated NASA administrator

Faced with dismal weather in Florida but a chance for improvement Sunday, the Atlantis astronauts were ordered to back out of landing preparations and to stay in orbit a second extra day in a row in hopes of getting back to Florida.

In Washington, meanwhile, the White House announced that former shuttle commander Charles F. Bolden Jr. will be nominated as NASA's next administrator, along with Lori Garver as his deputy, ending four months of speculation.

"These talented individuals will help put NASA on course to boldly push the boundaries of science, aeronautics and exploration in the 21st century and ensure the long-term vibrancy of America's space program," Obama said in a statement.

At the Johnson Space Center in Houston, flight controllers were in the process of revising their timelines and procedures to support a Sunday landing for Atlantis.

"Atlantis, the weather at KSC has not cooperated with us today," called astronaut Gregory H. Johnson from mission control in Houston. "There is a chance that we could land tomorrow at KSC and we're going to keep that option open. We are waving off for the day. Edwards remains good and it's a good option for both Sunday and Monday should the weather at KSC turn out to not favor us."

The astronauts will have two opportunities to land in Florida Sunday and two at Edwards. For first Florida opportunity, the astronauts would fire Atlantis' twin braking rockets at 8:58 a.m., setting up a landing around 10:11 a.m.

The astronauts had hoped to land Friday at the Kennedy Space Center, but rain, lightning and low clouds forced Knight to order a one-day waveoff in hopes of better conditions today. But Kennedy was socked in again, with low clouds and rain showers near the shuttle landing strip. The forecast for Sunday is marginal, with clouds and rain expected, but flight controllers are hopeful conditions will improve.


7:30 AM, 5/23/09, Update: Atlantis slips first Florida landing opportunity

Low clouds and rain at the Kennedy Space Center prompted entry Flight Director Norm Knight to pass up the shuttle Atlantis' first Florida landing opportunity today. The astronauts were told to take another 90-minute spin around the planet and to set up for landing opportunities at Edwards Air Force Base, Calif., or Kennedy if conditions improve.

"We've decided to wave off this rev," astronaut Gregory H. Johnson called from Houston just before 7 a.m. "KSC is observed and forecast no-go, it's got a very moist atmosphere, it's very dynamic and if there's any way we could get comfortable in the next 45 minutes of looking at it, we'd give it a chance. But we don't see that in our future. So we're going to hold off on fluid loading and we will get back with you."

"OK, Houston, understand, we will hold right where we are," commander Scott Altman replied from Atlantis.

The deorbit times for the crew's next two entry opportunities have changed slightly. The deorbit rocket firing for Edwards is targeted for 9:28:46 a.m. EDT, which would set up a landing around 10:45:09 a.m. Deorbit for Kennedy would come 15 minutes later, at 9:45:26 a.m., setting up a landing around 10:54:10 a.m.


4:20 AM, 5/23/09, Update: Astronauts prepare for re-entry

Commander Scott Altman and his crewmates, facing more stormy weather at the Kennedy Space Center, readied the shuttle Atlantis for a day-late re-entry Saturday while flight controllers assessed the forecast and options for landing in Florida or California.

The Atlantis astronauts have three landing opportunities in Florida and two in California on successive orbits, beginning with an 8:01:11 a.m. deorbit to the Kennedy Space Center for a touchdown at 9:15:15 a.m. One orbit later, the crew has a shot at an Edwards Air Force Base, Calif., landing at 10:44:56 a.m. and another Kennedy opportunity at 10:54:10 a.m.

"Unfortunately the weather pattern is very similar to yesterday," astronaut Gregory H. Johnson radioed from mission control just after 4 a.m. "But we're continuing to look at the weather. We'd call it marginal at this point. Our plan is to progress a little further into the deorbit prep timeline. We're thinking we're going to probably press down through (payload bay) door closure (around 5:20 a.m.). However, we're going to hold off suiting up for a little while until we can get a little more comfortable where we're headed."

"OK, copy that. Our tag-up points will be a little further along in the timeline and you plan on probably going through door closure," Altman replied. "But we appreciate the suit-up call."

The Spaceflight Meteorology Group at the Johnson Space Center in Houston is predicting a low, broken cloud deck at 4,000 feet and thundershowers within 30 nautical miles of the Kennedy runway. Flight rule violations include low ceilings, lightning, rain and thunderstorms. While the clouds are expected to lift a bit as the day wears on, thundershowers are expected in the vicinity during all three Kennedy opportunities.

The forecast for Edwards Air Force Base in California's Mojave Desert calls for generally clear skies and acceptable winds.

Atlantis has enough on-board supplies to remain in orbit through Monday. Entry Flight Director Norm Knight said Thursday he would consider keeping the astronauts in orbit until Sunday if the Florida forecast showed a clear, positive trend.

But the SMG is predicting more low clouds and thundershowers at Kennedy Sunday, raising the prospect of a diversion to Edwards later this morning. NASA managers try to avoid California landings if possible because it takes a week to 10 days to get a shuttle back to Florida and costs about $1.8 million. The primary issue, however, is the lost time processing the ship for its next flight. Atlantis is scheduled to fly again in November.

Seventy of NASA's 123 previous shuttle landings were at Kennedy while 52 were at Edwards. One shuttle mission ended at Northrup Strip, N.M., in 1982.

Repeating from Friday, here are timelines for the crew's first three landing opportunities today (in EDT; best viewed with fixed-width font):

EDT...........EVENT

Rev. 180 to KSC

TIG: 08:01:11 AM (dV: 174 mph; dT: 02:34)
Crossrange: 4.6 sm
Range to KSC at entry interface: 4,920 sm
Landing: 09:15:15 AM (KSC 15)

04:01 AM......Begin deorbit timeline
04:16 AM......Radiator stow
04:26 AM......Mission specialists seat installation
04:32 AM......Computers set for deorbit prep
04:36 AM......Hydraulic system configuration
05:01 AM......Flash evaporator checkout
05:07 AM......Final payload deactivation
05:21 AM......Payload bay doors closed
05:31 AM......Mission control 'go' for OPS-3
05:41 AM......OPS-3 transition
06:06 AM......Entry switchlist verification
06:16 AM......Deorbit PAD update
06:21 AM......Crew entry review
06:36 AM......CDR/PLT don entry suits
06:53 AM......IMU alignment
07:01 AM......CDR/PLT strap in; MS suit don
07:18 AM......Shuttle steering check
07:21 AM......Hydraulic system prestart
07:28 AM......Toilet deactivation
07:41 AM......Mission control center 'go' for deorbit burn
07:47 AM......Crew seat ingress
07:56 AM......Single APU start

08:01:11 AM...Deorbit ignition
08:03:45 AM...Deorbit burn complete

08:43:55 AM...Entry interface (76 miles)
08:48:24 AM...1st roll command to right
08:55:15 AM...1st right-to-let roll reversal
09:02:15 AM...C-band radar acquisition
09:09:49 AM...Velocity less than mach 2.5 (82,300 feet)
09:10:58 AM...Velocity less than mach 1 (47,500 feet)
09:11:19 AM...Shuttle on the HAC (42,300 feet; 298-degree left turn)
09:15:15 AM...Landing on runway 15

---------------------------------------

Rev. 181 Deorbit to EDW

TIG: 09:29:11 AM (dV: 188 mph; dT: 2:46)
Crossrange: 452 sm
Range to EDW at entry interface: 4,856 sm
Landing: 10:44:56 AM (EDW 22)

09:09 AM......MCC 'go' for deorbit burn
09:15 AM......MS seat ingress
09:24 AM......Single APU start

09:29:11 AM...Deorbit ignition
09:31:57 AM...Deorbit burn complete

10:14:06 AM...Entry interface
10:18:35 AM...1st roll command to left
10:29:38 AM...1st left-to-right roll reversal
10:38:43 AM...Velocity less than mach 2.5
10:40:54 AM...Velocity less than mach 1
10:41:53 AM...Shuttle on the HAC (197-degree turn)
10:44:56 AM...Landing

---------------------------------------

Rev. 181 Deorbit to KSC

TIG: 09:44:56 AM (dV: 165 mph; dT: 2:26)
Crossrange: 221 sm
Range to KSC at entry interface: 4,941 sm
Landing: 10:54:10 AM (KSC 15)

09:24 AM......MCC 'go' for deorbit burn
09:30 AM......MS seat ingress
09:39 AM......Single APU start

09:44:56 AM...Deorbit ignition
09:47:22 AM...Deorbit burn complete

10:22:48 AM...Entry interface
10:27:17 AM...1st roll command to left
10:36:19 AM...1st left-to-right roll reversal
10:47:46 AM...Velocity less than mach 2.5
10:49:54 AM...Velocity less than mach 1
10:50:08 AM...Shuttle on the HAC (310-degree turn
10:54:10 AM...Landing


6:45 PM, 5/22/09, Update: Updated Saturday landing times; entry timeliness

Flight controllers at the Johnson Space Center in Houston have updated the landing times for the shuttle Atlantis on Saturday. The astronauts have three possible shots at a Florida landing and three in California, but NASA would only take advantage of the best two or three of those after factoring in the weather. As of this writing, landing is targeted for the first Florida opportunity at 9:15:15 a.m.

Here are timelines for the first three landing opportunities, two at the Kennedy Space Center and one at Edwards Air Force Base, Calif. (in EDT; best viewed with fixed-width font). Timelines for all of the possible opportunities are available on the CBS News STS-125 Quick-Look page:

http://www.cbsnews.com/network/news/space/currentglance.html

EDT...........EVENT

Rev. 180 to KSC

TIG: 08:01:11 AM (dV: 174 mph; dT: 02:34)
Crossrange: 4.6 sm
Range to KSC at entry interface: 4,920 sm
Landing: 09:15:15 AM (KSC 15)

04:01 AM......Begin deorbit timeline
04:16 AM......Radiator stow
04:26 AM......Mission specialists seat installation
04:32 AM......Computers set for deorbit prep
04:36 AM......Hydraulic system configuration
05:01 AM......Flash evaporator checkout
05:07 AM......Final payload deactivation
05:21 AM......Payload bay doors closed
05:31 AM......Mission control 'go' for OPS-3
05:41 AM......OPS-3 transition
06:06 AM......Entry switchlist verification
06:16 AM......Deorbit PAD update
06:21 AM......Crew entry review
06:36 AM......CDR/PLT don entry suits
06:53 AM......IMU alignment
07:01 AM......CDR/PLT strap in; MS suit don
07:18 AM......Shuttle steering check
07:21 AM......Hydraulic system prestart
07:28 AM......Toilet deactivation
07:41 AM......Mission control center 'go' for deorbit burn
07:47 AM......Crew seat ingress
07:56 AM......Single APU start

08:01:11 AM...Deorbit ignition
08:03:45 AM...Deorbit burn complete

08:43:55 AM...Entry interface (76 miles)
08:48:24 AM...1st roll command to right
08:55:15 AM...1st right-to-let roll reversal
09:02:15 AM...C-band radar acquisition
09:09:49 AM...Velocity less than mach 2.5 (82,300 feet)
09:10:58 AM...Velocity less than mach 1 (47,500 feet)
09:11:19 AM...Shuttle on the HAC (42,300 feet; 298-degree left turn)
09:15:15 AM...Landing on runway 15

---------------------------------------

Rev. 181 Deorbit to EDW

TIG: 09:29:11 AM (dV: 188 mph; dT: 2:46)
Crossrange: 452 sm
Range to EDW at entry interface: 4,856 sm
Landing: 10:44:56 AM (EDW 22)

09:09 AM......MCC 'go' for deorbit burn
09:15 AM......MS seat ingress
09:24 AM......Single APU start

09:29:11 AM...Deorbit ignition
09:31:57 AM...Deorbit burn complete

10:14:06 AM...Entry interface
10:18:35 AM...1st roll command to left
10:29:38 AM...1st left-to-right roll reversal
10:38:43 AM...Velocity less than mach 2.5
10:40:54 AM...Velocity less than mach 1
10:41:53 AM...Shuttle on the HAC (197-degree turn)
10:44:56 AM...Landing

---------------------------------------

Rev. 181 Deorbit to KSC

TIG: 09:44:56 AM (dV: 165 mph; dT: 2:26)
Crossrange: 221 sm
Range to KSC at entry interface: 4,941 sm
Landing: 10:54:10 AM (KSC 15)

09:24 AM......MCC 'go' for deorbit burn
09:30 AM......MS seat ingress
09:39 AM......Single APU start

09:44:56 AM...Deorbit ignition
09:47:22 AM...Deorbit burn complete

10:22:48 AM...Entry interface
10:27:17 AM...1st roll command to left
10:36:19 AM...1st left-to-right roll reversal
10:47:46 AM...Velocity less than mach 2.5
10:49:54 AM...Velocity less than mach 1
10:50:08 AM...Shuttle on the HAC (310-degree turn
10:54:10 AM...Landing


8:10 AM, 5/22/09, Update: Shuttle landing attempt called off; entry delayed to at least Saturday

After waving off the shuttle Atlantis' re-entry by one orbit because of dismal weather, entry Flight Director Norm Knight threw in the towel shortly before 8 a.m., calling off a second attempt and retargeting landing for Saturday.

"We're going to formally wave off for the day," astronaut Gregory H. Johnson called from mission control around 7:50 a.m. "The weather at KSC is quite unstable. KSC is no-go and forecast no-go with (rain) within 30 (nautical miles) and low ceilings and showers are consistently popping up off shore and over land. We don't see any value in waiting two or three hours, so we're going to wave off for the day."

The Atlantis astronauts will have four possible landing opportunities Saturday, two at the Kennedy Space Center and two at Edwards Air Force Base, Calif., although no decision has been made as to whether Edwards would be used.

The Florida forecast calls for a chance of showers Saturday and possibly low ceilings, If that holds up, and if conditions Sunday look promising, the shuttle mission could be extended one more day in hopes of getting Atlantis back to Kennedy. Otherwise, the crew likely would head for Edwards on Saturday. But as of this writing, no decisions have been made.

Here are all the deorbit and landing times for Saturday (in EDT):

ORBIT...SITE...DEORBIT BURN...LANDING

180.....KSC....08:02 AM.......09:16 AM
181.....EDW....09:29 AM.......10:46 AM
........KSC....09:46 AM.......10:54 AM
182.....EDW....11:12 AM.......12:24 PM


6:00 AM, 5/22/09, Update: WAVEOFF! Shuttle entry delayed by at least one orbit

Dismal weather at the Kennedy Space Center prompted entry Flight Director Norm Knight to delay the shuttle Atlantis' planned re-entry by at least one orbit. The only remaining landing opportunity today calls for a de-orbit rocket firing at 10:33:41 a.m., setting up a landing on runway 15 at 11:39:18 a.m. If the weather or some other problem prevents a re-entry today, the crew will remain in orbit another 24 hours and try again on Saturday.

"We are going to ... wave off this attempt and we will pass you further words when we get them," astronaut Gregory H. Johnson radioed from mission control. "The weather just is not clearing up at the Cape at this point."

"OK, Houston, we appreciate you making the early call," replied shuttle commander Scott Altman. "Understand we can basically just hold here, don't need any de-orbit backout."

"That's affirmative," Johnson replied. "We will just proceed from here."

NASA has run into problems with one of its Tracking and Data Relay System communications satellites and Johnson warned Altman about possible breaks in radio coverage.

Here is a timeline of major entry events for the crew's second and final landing opportunity today (in EDT; best viewed with fixed-width font):

EDT...........EVENT

Rev. 166 Deorbit to KSC

10:13 AM......Mission control 'go' for deorbit burn
10:19 AM......Astronaut seat ingress
10:28 AM......Single hydraulic power unit start

10:33:41 AM...Deorbit ignition (dT: 2:34; dV: 173 mph)
10:36:15 AM...Deorbit burn complete (alt: 345 miles)

11:07:56 AM...Atmospheric entry (alt: 76 sm; range: 4,944 sm)
11:12:27 AM...1st roll command to left
11:22:01 AM...1st left-to-right roll reversal
11:32:54 AM...Velocity less than mach 2.5 (alt: 82,000 feet)
11:35:01 AM...Velocity less than mach 1 (alt: 47,800 feet)
11:35:17 AM...Shuttle banks to line up on runway (alt: 42,700 feet)
11:39:18 AM...Landing


5:00 AM, 5/22/09, Update: Astronauts gear up for landing

Keeping tabs on threatening weather, the Atlantis astronauts rigged the shuttle for re-entry and landing today to wrap up a successful mission to service the Hubble Space Telescope.

"Good morning, entry team," commander Scott Altman radioed mission control around 4 a.m., after the morning shift change. "Looking forward to doing it with you today."

"We are as well," astronaut Gregory H. Johnson replied from Houston. Despite a dismal forecast, he added "we are hopeful the weather will clear up nicely."

Altman, pilot Gregory C. Johnson, flight engineer Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good have two landing opportunities today at the Kennedy Space Center, the first at 10:00:39 a.m. and the second at 11:39:18 a.m.

There are no technical problems of any significance with Atlantis, but the morning forecast from the Spaceflight Meteorology Group at the Johnson Space Center called for a broken deck of clouds at 4,000 feet and thundershowers within 30 nautical miles of the runway, both violations of NASA's entry flight rules. The wind is expected to be out of the east at 12 knots, gusting to 19, producing crosswinds just below NASA's 15-knot limit.

"We have just talked to the weather folks and what we've got in Florida is a very dynamic situation," Johnson said just before 5 a.m. "There are thunderstorms that are stretching from the southeast over Bermuda to the northwest and going through the circle, the 30-nautical-mile circle around the Cape. There are some clear areas to the south and we think over time, that line could move a little north or it might stay the same. The air is saturated.

"We're also looking at ceilings, the crosswind is just right at the limit, so there are a lot of issues against us. However, it's a dynamic situation and we're going to keep our eyes on it closely. We view our next decision point, based on the weather, just prior to payload bay door closing (around 6:10 a.m.). And so, we'll get a better update on the weather at that point and our plan is to press on, at least up to that point, in deorbit prep. How copy?"

"Houston, copy that, understand the Cape weather system that's there and the dynamics that are involved," Altman replied. "We concur, we're pressing ahead, we'll have another tag-up at payload bay door closing."

Assuming they're cleared to close the doors, the entry day timeline calls for the astronauts to begin donning their bulky pressure suits just before 7:30 a.m.

"If it's clearly a no-go, we're not going to put the crew through suit-up just for practice," entry Flight Director Norm Knight said Thursday. "They know how to do it and we'll back out at the appropriate time, go around a rev (orbit) if needed, look at the next opportunity and make a decision if we think that's the rev we want to target or not.

"So it's really a function of what the weather's looking like, how bad it is and if we think we have a shot. If we think we have a shot, we'll march down all the way and execute the (deorbit) burn if it's the safe thing to do.

NASA is not staffing its backup landing site at Edwards Air Force Base, Calif., and if the weather or some other problem prevents a Florida landing today, the crew will remain in orbit another 24 hours and try again Saturday. In that case, Edwards would be staffed.

The shuttle has enough on-board supplies to keep the ship powered through Monday, but if the doesn't get home today, and if the forecast for Florida remains unfavorable through the weekend, Knight could opt to bring the crew down Saturday in California. The forecast for Edwards is "go" all weekend.

Repeating from Thursday, here is a timeline of major entry events for both of today's landing opportunities (in EDT; best viewed with fixed-width font):

EDT...........EVENT

Rev. 165 Deorbit to KSC

04:49 AM......Begin deorbit timeline
05:04 AM......Radiator stow
05:14 AM......Mission specialists seat installation
05:20 AM......Computers set for deorbit prep
05:24 AM......Hydraulic system configuration
05:49 AM......Flash evaporator cooling system checkout
05:55 AM......Final payload deactivation
06:09 AM......Payload bay doors closed
06:19 AM......Mission control 'go' for OPS-3 entry software load
06:29 AM......OPS-3 transition
06:54 AM......Entry switchlist verification
07:04 AM......Deorbit maneuver update
07:09 AM......Crew entry review
07:24 AM......CDR/PLT don entry suits
07:41 AM......IMU alignment
07:49 AM......CDR/PLT strap in; MS suit don
08:06 AM......Shuttle steering check
08:09 AM......Hydraulic system prestart
08:16 AM......Toilet deactivation

08:29 AM......Mission control 'go' for deorbit burn
08:35 AM......Astronaut seat ingress
08:44 AM......Single APU start

08:49:16 AM...Deorbit ignition (dT: 2:28; dV: 167 mph)
08:51:44 AM...Deorbit burn complete (alt: 345 miles)

09:29:09 AM...Atmospheric entry (alt: 76 sm; vel: 16,840 mph; range: 4,925 sm)
09:33:36 AM...1st roll command to right
09:40:23 AM...1st right-to-let roll reversal
09:48:00 AM...C-band radar acquisition
09:54:05 AM...Velocity less than mach 2.5 (alt: 82,000 feet)
09:56:13 AM...Velocity less than mach 1 (alt: 47,800 feet)
09:56:33 AM...Shuttle on the HAC (alt: 42,700 feet)
10:00:31 AM...Landing

Rev. 166 Deorbit to KSC

10:13 AM......Mission control 'go' for deorbit burn
10:19 AM......Astronaut seat ingress
10:28 AM......Single APU start

10:33:41 AM...Deorbit ignition (dT: 2:34; dV: 173 mph)
10:36:15 AM...Deorbit burn complete (alt: 345 miles)

11:07:56 AM...Entry interface (alt: 76 sm; range: 4,944 sm)
11:12:27 AM...1st roll command to left
11:22:01 AM...1st left-to-right roll reversal
11:32:54 AM...Velocity less than mach 2.5 (alt: 82,000 feet)
11:35:01 AM...Velocity less than mach 1 (alt: 47,800 feet)
11:35:17 AM...Shuttle on the HAC (alt: 42,700 feet)
11:39:18 AM...Landing


03:45 PM, 5/21/09, Update: Endeavour released from rescue duty; flight director outlines Atlantis landing strategy

With the shuttle Atlantis in good shape and no problems with its protective heat shield, NASA managers today released the shuttle Endeavour from stand-by duty for a possible launch on an emergency rescue mission.

Engineers at the Kennedy Space Center started a countdown Wednesday to preserve the option of launching Endeavour this weekend if some major problem developed that might prevent Atlantis from making a safe re-entry.

The Atlantis astronauts, launched into the Hubble Space Telescope's orbit, cannot seek "safe haven" aboard the International Space Station and NASA managers decided early on to prepare Endeavour for possible rescue duty in case of heat shield damage or some other major malfunction aboard Atlantis.

But Atlantis sailed through routine re-entry tests earlier today, its heat shield is in good condition and with bad weather threatening a landing delay to Saturday or possibly even Sunday, there was little point in continuing Endeavour's countdown.

For Endeavour to reach Atlantis now, it would have to take off Saturday or Sunday at the latest. Atlantis only has enough hydrogen and oxygen for its fuel cell system to make it through Monday and it would take Endeavour two days to complete a rendezvous. As a result of all that, mission managers released Endeavour from rescue stand by, clearing the way for normal processing toward launch June 13 on a space station assembly mission.

NASA managers never expected to actually need a rescue mission, saying improved post-Columbia damage detection and repair techniques could handle the sorts of heat shield damage that might be reasonably expected, even in Hubble's higher, more debris-littered orbit. As it turned out, no such damaged has been seen.

The Atlantis astronauts, meanwhile, spent the morning testing the shuttle's re-entry systems and preparing for landing Friday, weather permitting.

"That all checked out perfect, we're ready to go, the vehicle is clearly ready for entry," said entry flight director Norm Knight.

During launch May 11, a short circuit knocked out one of four redundant electronic boxes used to format computer commands to valves that provide hydraulic power to actuators that, in turn, drive the shuttle's elevons, body fly and rudder/speed brake. Flight controllers checked out the aerosurface actuators today and verified Atlantis has no problems of any significance.

"There are four of these ASAs, we've lost one of the four, we're still fully functional and ready to go," Knight said. "We checked the rest of the system out today and have no issues."

Because Atlantis has enough on-board supplies to remain in orbit through Monday, Knight said the agency did not plan to staff the shuttle's backup landing site at Edwards Air Force Base, Calif., on Friday. Instead, the crew will have just two landing opportunities at the Kennedy Space Center, one at 10:00:39 a.m. and the other one orbit later at 11:39:18 a.m. If the weather or some other problem prevents re-entry, the crew will stay in orbit another day and try again Saturday.

"The weather for KSC on Friday, I'll tell you it doesn't look great," Knight said. "There's a low pressure (system) sitting over Central Florida, it's been sitting there for several days, Florida's received quite a bit of rain and we're just waiting for that system to move out. So it's really a matter of timing as to when that system is going to move.

"We expect it's going to improve over the next couple of days, but again, it's just a matter of waiting and seeing. The entry strategy, based on the fact that we have end-of-mission-plus-three (days), is to target KSC only tomorrow, so we're not going to target Edwards, and then on Saturday we'll bring up Edwards, we'll look at both KSC and Edwards and really, based on how the weather is on Sunday, make a determination if Saturday is the day we're going to land."

The forecast for Edwards is "go" through the weekend, while rain is expected at NASA's other backup landing field, Northrup Strip, N.M.


7:35 AM, 5/21/09, Update: Atlantis astronauts pack up, test re-entry systems

The Atlantis astronauts tested the shuttle's re-entry systems early Thursday and began packing for landing Friday, weather permitting, to close out a successful mission to overhaul the Hubble Space Telescope. The flight plan calls for a de-orbit rocket firing at 8:49:16 a.m. Friday, setting up a landing on runway 15 at the Kennedy Space Center at 10:00:31 a.m. A second landing opportunity is available one orbit later, at 11:39:18 a.m.

With no major technical problems in orbit, the only question mark is the weather, with forecasters predicting a broken cloud deck at 4,000 feet, crosswinds above 15 knots and a chance of thundershowers within 30 nautical miles of the runway, all violations of NASA's landing weather flight rules.

High winds and torrential rains rumbled through the area overnight as severe thunderstorms lashed Florida's Space Coast. There is a 50 percent chance of heavy rain, high winds and thundershowers all day Thursday and more of the same expected overnight and Friday.

But the astronauts have conserved power and now have saved enough hydrogen and oxygen to power the ship's electricity producing fuel cells through Monday. As a result, NASA is not staffing backup landing sites Friday. If the weather or some other issue blocks the two available landing opportunities, the crew will stay in orbit an extra day and try again Saturday.

Hoping for the best, commander Scott Altman, pilot Gregory C. Johnson and flight engineer Megan McArthur tested Atlantis' re-entry systems, firing up a hydraulic power unit, exercising the orbiter's aerosurfaces and test-firing the ship's small maneuvering thrusters. There were no problems.

The crew plans to take a call from Sen. Barbara Mikulski, D-MD, at 12:31 p.m. to discuss the crew's overhaul of the space telescope. Mikulski, a long-time Hubble booster, represents the Goddard Space Flight Center in Greenbelt, MD, and the Space Telescope Science Institute at Johns Hopkins University in Baltimore.

Later in the day, starting at 2:41 p.m., the astronauts will participate in round-robin interviews with CBS News and other networks.

Today's mission status briefing with entry flight director Norm Knight is scheduled for 3:15 p.m., although it may be moved up to 1 p.m. The astronauts plan to go to bed at 6:01 p.m. and to get up Friday at 2:01 a.m. to begin landing preparations.

Here is an updated timeline of today's activity (in EDT and mission elapsed time; includes revision J of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05/21/09
03:01 AM...09...13...00...Crew wakeup
06:01 AM...09...16...00...Cabin stow begins
06:11 AM...09...16...10...Flight control system checkout
07:21 AM...09...17...20...RCS hotfire
07:36 AM...09...17...35...Entry video setup
07:56 AM...09...17...55...PILOT landing practice
09:41 AM...09...19...40...Joint crew meal
09:51 AM...09...19...50...Deorbit review
10:41 AM...09...20...40...Cabin stow resumes
11:51 AM...09...21...50...L-1 comm check
12:31 PM...09...22...30...PAO event with Sen. Barbara Mikulski
12:51 PM...09...22...50...Crew photo
01:00 PM...09...22...59...Mission status briefing (presumed)
02:21 PM...10...00...20...Wing leading edge sensor system deactivation
02:21 PM...10...00...20...PGSC stow (part 1)
02:41 PM...10...00...40...CBS,ABC,NBC,FOX,CNN crew interviews
03:06 PM...10...01...05...Ergometer stow
03:06 PM...10...01...05...KU antenna stow
04:00 PM...10...01...59...LRO/LCROS lunar mission briefing on NTV
06:01 PM...10...04...00...Crew sleep begins
07:00 PM...10...04...59...Daily highlights reel on NTV


7:10 PM, 5/20/09, Update: Atlantis heat shield cleared for entry; Obama hails successful Hubble repair, promises new administrator 'soon'

President Barack Obama called the crew of the shuttle Atlantis late Wednesday and congratulated the astronauts on the successful overhaul of the Hubble Space Telescope. He also promised to name a new NASA administrator soon, although he provided no clues as to who might get the nod.

"We're soon going to have a new NASA administrator," Obama told the astronauts. "I can't disclose it to you because I've got to have some hoopla on the announcement back here on Earth. But I can assure you that it's a high priority of mine to restore that sense of wonder that space can provide and to make sure we've got a strong sense of mission, not just within NASA but to the country as a whole."

Atlantis commander Scott Altman jokingly asked the president, "just so we're sure, the new administrator's not any of us on the flight deck right now, is it?"

Obama laughed, and said "I'm not going to give you any hints."

"Thank you very much, fair enough, sir," Altman said.

Charles F. Bolden Jr., a former fighter pilot, Marine Corps major general and veteran space shuttle commander, is widely rumored to be the top candidate for the job. Bolden met with Obama at the White House on Tuesday.

During today's phone call to the Atlantis astronauts, Obama said "I wanted to personally tell you how proud I am of all of you and everything that you've accomplished."

"Like a lot of Americans, I've been watching with amazement the gorgeous images you've been sending back and the incredible repair mission you've been making in space," he said. "I think you're providing a wonderful example of the kind of dedication and commitment to exploration that represents America and the space program generally. These are traits that have always made this country strong and all of you personify them."

"Well thank you very much, sir," Altman replied. "I think you are exactly right, this mission has been an example of what our country can do as we work together. It's been the teamwork of all the folks on the ground, in addition to the folks outside spacewalking, making this all come together and work for us."

The president said watching the Hubble repair spacewalks was "amazing, and Dr. Grunsfeld, I was moved by your observation that the Hubble is more than just a satellite, but an iconic symbol of our quest for knowldge. I thought that captures accurately the work that you guys are doing."

Lead spacewalker John Grunsfeld told Obama "it's almost impossible to go into any K-through-12 classroom these days and not see Hubble images on the walls, inspiring kids to do great things and maybe some of them to become astronauts some day and push our frontiers even further."

"Well, I know you've excited my 10-year-old and my 7-year-old," Obama said. "By allowing Hubble to continue on its journey, you've really allowed all of us to continue on our journey of growth and exploration. You know, here in Washington, there's a lot of talk about clarifying our focus, our vision for where the country needs to go. And I really think that what you guys represent is an example of what 'vision' means.

"The space program's always described our willingness to stretch beyond current boundaries and to look at things in new ways," Obama said. "So in that way, you inspire us all and I'm hoping you guys recognize how important your mission is to the world as well as to this country."

NASA's Mission Management Team, meanwhile, completed a detailed review of imagery and laser scans from a late inspection of the shuttle Atlantis' heat shield Tuesday. MMT Chairman LeRoy Cain said the team gave Atlantis a clean bill of health and cleared the ship for re-entry and landing Friday, weather permitting.

"In the Mission Management Team (meeting) today, we had the opportunity to review the results," said MMT Chairman LeRoy Cain. "As you know, yesterday the crew performed the late inspection of the wing leading edge and the reinforced carbon carbon of the nose cap. They pored over all that data throughout the evening and this morning, and at the Mission Management Team today, they reviewed that data with us and the results are we don't have any issues as it relates to the thermal protection system ... So we have cleared the TPS and the vehicle for safe deorbit, entry and landing. That was a great milestone for us."

Landing currently is targeted for 10:01 a.m. Friday at the Kennedy Space Center. But forecasters are predicting a chance of low clouds and rain in the area and as a precaution, the astronauts were asked to power down non-essential equipment Wednesday to conserve hydrogen and oxygen used by the shuttle's fuel cell system to generate electricity.

As it now stands, the crew will have enough supplies to remain in orbit three days beyond Friday. NASA does not plan to staff its backup landing site at Edwards Air Force Base, Calif., on Friday, but depending on the weather, backup sites could be activated Saturday if necessary.

At the Kennedy Space Center, engineers are continuing to work through a countdown to ready the shuttle Endeavour for launch on an emergency rescue mission if a major problem crops up that might prevent a safe re-entry.

Because the Atlantis astronauts cannot reach the International Space Station for "safe haven," Endeavour has been prepped for a quick-response launch if needed.

Going into the Hubble Space Telescope repair mission, NASA managers planned to release Endeavour from rescue stand by duty after Atlantis' heat shield was cleared for entry.

But Cain said he decided to keep Endeavour on standby at least through Thursday and possibly as late as Atlantis' deorbit rocket firing Friday "because I can, and it doesn't affect (Endeavour's next flight in June)."

"I was willing to go as late as deorbit on Friday," he said. "I'm going to evaluate that again tomorrow."

Because Atlantis is near the end of its mission, most of its on-board supplies have been used up and even with the power downs implemented today, the crew will run out of oxygen for its fuel cells by some point late Monday or Tuesday. For Endeavour to have any chance of reaching the crew in time, should something prevent a normal re-entry, the rescue shuttle would have to take off by Saturday or Sunday at the latest.

Cain said mission managers do not anticipate any such problems and expect Atlantis to make a normal re-entry on its own. But in the meantime, NASA is protecting its options as planned.


1:20 PM, 5/20/09, Update: With rainy weather expected, astronauts conserve power in case Friday landing delayed

With rainy weather possible in Florida on Friday, the Atlantis astronauts were asked to power down less-critical equipment Wednesday to conserve hydrogen and oxygen for the shuttle's fuel cell system in case landing is delayed. Touchdown currently is planned for 10:01 a.m. Friday, but additional opportunities on both coasts are available Saturday and Sunday.

With the power downs, "that puts us about 21 hours above an 11 (days) plus two (extension days), which gives us a lot of margin down the road as we keep an eye on the weather," astronaut Dan Burbank radiod the crew. "Certainly, we're all hoping for the best here and that we'll get you home on Friday. That's still our hope."

The Spaceflight Meteorology Group at the Johnson Space Center in Houston is predicting scattered clouds at 4,000 feet at landing time Friday, a broken deck at 10,000 feet, a chance of broken clouds at 4,000 feet and a chance of thundershowers within 30 nautical miles of the shuttle runway.

NASA's Mission Management Team, meanwhile, is wrapping up analysis of a heat shield inspection carried out by the crew Tuesday. While the assessment was not yet officially complete, Burbank told commander Scott Altman there were no signs of trouble.

"We have one bit of good news," he reported. "All the imagery from the late inspection has been reviewed. Now, we still have to finish out the final reviews on it, but there are zero areas of interest."

"OK, copy, Houston, thanks. Zero areas of interest," Altman said.

During a traditional on-orbit crew news conference earlier Wednesday, Altman said he was confident Atlantis would be cleared for entry as is.

"We did a pretty complete survey yesterday," he told CBS News. "I was very happy with all the imagery and the activity that we had to make sure we got as good an inspection as possible. We used the sun to help us inspect both the wings to make sure we had better pictures of the leading edge of our wings for re-entry.

"So I feel very confident we have all the data that we need, I'm letting the experts crunch that (data) to make sure everything looks good. From our vantage point, we think it's probably looking very good for entry and we're looking forward to that."

LeRoy Cain, chairman of the MMT and deputy shuttle program manager at the Johnson Space Center, planned to brief reporters later today on the status of the on-going heat shield assessment and NASA's strategy for keeping the shuttle Endeavour on stand by for a possible rescue mission if any major problems are discovered between now and re-entry.

Endeavour has been poised atop pad 39B at the Kennedy Space Center, ready since Monday for the start of a three-day countdown to launch if needed. Early today, engineers protectively started a rescue mission countdown to preserve the option of launching Endeavour as soon as possible if problems develop.

Mission managers originally planned to release Endeavour from rescue stand-by duty after the final heat shield inspection, but they have decided to continue Endeavour's processing until Atlantis successfully fires its braking rockets to drop out of orbit. Given the prospects for bad weather Friday, that could happen as late as Saturday or Sunday, in a worst-case scenario, leaving NASA little time to launch Endeavour. Hence the decision to start conserving power.

Assuming the MMT clears Atlantis' heat shield for entry, an extended "hold" will be inserted in Endeavour's countdown before fuel cell loading early Thursday. No one expects a rescue mission to be needed, but NASA is keeping all options open until Atlantis successfully begins the trip home.

The Atlantis astronauts successfully overhauled and upgraded the Hubble Space Telescope during five back-to-back spacewalks, installing two new instruments, repairing two others, replacing six gyroscopes, six batteries, a star sensor and a science data computer. They also attached three new insulation panels to improve temperature control.

The telescope was released back into open space early Tuesday and the astronauts took the day off Wednesday to relax and enjoy the view from 350 miles up. Shortly after noon, flight controllers arranged for the shuttle astronauts to chat with the three-man crew of the International Space Station.

"Hello Atlantis, this is International Space Station, we're very glad to welcome you guys," station commander Gennady Padalka called from 220 miles above Europe.

"Hey, and greetings to you all," Altman replied as the shuttle sailed high above the central Atlantic Ocean.

"It's very wonderful to talk to you guys," called Japanese astronaut Koichi Wakata. "Congratulations on the wonderful (Hubble servicing) EVAs. You guys did an outstanding job."

Station flight engineer Michael Barrett said the lab crew had followed the exploits of the Hubble mission and "it's just the greatest thing to see these two remarkable machines made by such remarkable people coming together again, this time for the last time."

"We wanted to offer some heartfelt congratulations for a job well done," he said. "We also know how hard you guys have been training and how personally invested in this great telescope you've all been. I guess we all kind of envy you the chance to touch Hubble one final time and get her all commissioned for another several years of discovery. Again, we just think you guys have done an awesome job. It's great to hear laughter in the background, we know how intensively you've been working."

"Thanks, Mike, we've had a great time up here," shuttle robot arm operator Megan McArthur said. "It's really fun to be sharing space with you."

Late this afternoon, sources said, Altman and his crewmates may take a private phone call from President Obama.

Asked during their news conference what the crew would advise the president about NASA's future, Altman joked he would suggest making lead Hubble spacewalker John Grunsfeld the next NASA administrator.

Answering the question, Grunsfeld said he would tell the president that the "core mission of NASA is actually a pretty good one."

"When President Obama is briefed by the new (yet-to-be-named) administrator on all the things that NASA does, I think he'll be incredibly impressed by the breadth of things that we do in climate work, Earth observation, aeronautics, space science, all those things that have been our core strengths.

"And in human spaceflight, as much as we love low-Earth orbit, it's time to leave low-Earth orbit, go out and explore the cosmos. ... We have lots of places near by, near-Earth objects, the moon, Mars, it's a great solar system and it's time for humans to start moving out. And that's what we're (planning). What we have to do is get down to the business of actually doing it. And I think that's what I would say to President Obama."


8:30 AM, 5/20/09, Update: Astronauts enjoy off-duty day; crew news conference on tap; Endeavour on rescue stand by through deorbit burn Friday

With the Hubble Space Telescope safely on its way after a successful overhaul, the Atlantis astronauts enjoyed a day off Wednesday, relaxing after five back-to-back spacewalks. A replay of video from camera mounted in the shuttle's twin solid-fuel boosters is expected at 9 a.m., followed by a traditional crew news conference at 10:26 a.m.

LeRoy Cain, chairman of NASA's Mission Management Team, is scheduled to brief reporters at 4 p.m. on the results of a detailed heat shield inspection carried out by the astronauts Tuesday, after Hubble's release. As of early Wednesday, the assessment was about 70 percent complete.

Because the Atlantis astronauts cannot seek "safe haven" aboard the International Space Station if major problems develop that might prevent a safe re-entry, the shuttle Endeavour has been poised atop pad 39B at the Kennedy Space Center, ready since Monday for the start of a three-day countdown to launch if needed.

In a change of plans, mission managers have decided not to release Endeavour from rescue stand-by duty until Atlantis completes its deorbit rocket firing Friday. Touchdown at the Kennedy Space Center is targeted for 10:01 a.m.

Atlantis is now late in its mission, and on-board supplies will be in relatively short supply by the time the shuttle heads home Friday. If a major problem develops in the final stages of the flight, NASA would need to get Endeavour off the ground as fast as possible. As a result, engineers started a countdown at 6 a.m. Wednesday to make sure the ship can be launched in time if needed.

If the MMT clears Atlantis' heat shield for entry, the countdown will go into an extended "hold" before the start of fuel cell loading early Thursday and again early Friday if no problems develop. After Atlantis drops out of orbit, Endeavour will be released from rescue stand by and engineers will begin processing the shuttle for launch June 13 on a space station assembly mission.

NASA originally planned to release Endeavour from stand-by duty after Atlantis' late inspection. In any case, no major problems have been found so far with Atlantis and mission managers are gearing up for a normal landing Friday.

The biggest concern at this point is the weather, with forecasters predicting a chance of showers within 30 nautical miles of the runway. To give the crew an additional morning opportunity, and a better chance of beating afternoon clouds and showers, the astronauts Tuesday lowered one side of the shuttle's 350-mile-high circular orbit to 184 miles. Along with reducing the odds of a space debris impact by about 15 percent, the orbit adjustment brought in an earlier landing opportunity Friday.

The astronauts now have three possible landing opportunities on successive orbits Friday, but only the first two likely would be used.

Here is an updated timeline of today's activity (in EDT and mission elapsed time; includes revision I of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05/20/09
04:01 AM...08...14...00...Crew wakeup
07:01 AM...08...17...00...Crew off duty
09:00 AM...08...18...59...SRB camera launch footage replay on NTV
10:26 AM...08...20...25...Crew news conference
11:06 AM...08...21...05...Joint crew meal
12:06 PM...08...22...05...Shuttle-to-ISS call
12:21 PM...08...22...20...Crew off duty
04:00 PM...09...01...59...Post-MMT briefing on NTV
04:01 PM...09...02...00...HD downlink opportunity
07:01 PM...09...05...00...Crew sleep begins
08:00 PM...09...05...59...Daily video highlights reel on NTV


5:15 PM, 5/19/09, Update: Hubble scientist criticizes NASA's post-shuttle Constellation program; laments shuttle retirement

With the space shuttle facing retirement next year after eight more flights - and with the program basking in the success of its fifth and final mission to overhaul the Hubble Space Telescope - one of the observatory's senior scientists Tuesday lamented the loss of the winged orbiters in favor of new, less capable rockets.

David Leckrone, answering questions at a space shuttle mission status briefing following the release of the Hubble Space Telescope from shuttle Atlantis, criticized the agency's post-shuttle Constellation program and what he said was a lack of leadership and innovation.

Asked about lessons learned from the Hubble-shuttle partnership and the value of being able to service payloads in orbit, Leckrone said "I'm not going to be around all that much longer, I've had a very long career at NASA so I think I can speak fairly bluntly."

"I think the ability of space-suited human beings, seven of them, flying in a spaceship carrying a very, very heavy cargo, 20,000, 30,000 pounds, to low-Earth orbit, to then be able to go out in spacesuits and perform extraordinarily intricate operations ... and do it successfully, I think that is one of the most remarkable achievements that NASA has ever done," he said.

"And it just makes me want to cry to think that this is the end of it. There is no person out there, no leadership out there, there's no vision out there to pick up the baton that we're about to hand off and carry it forward. And I think that's just a shame, to abandon one of the most impressive, refined, sophisticated capabilities that this agency as a whole, human side and robotics side, has achieved."

Leckrone, senior Hubble project scientist at NASA's Goddard Space Flight Center, said giving up the space shuttle represents a "long-term loss of hard-won capability and costly capability."

"If there's a future for this agency, it's got to be in an innovative direction like that," he said. "We can't just keep doing the same old thing year after year. It's just not as productive as it could be otherwise. So, that's my piece. And I'm sticking with it."

NASA is in the process of completing the International Space Station before retiring the shuttle next year. The agency's Constellation program calls for building new Ares 1 rockets and Orion crew capsules to boost astronauts to low-Earth orbit starting in 2015. A new heavy lift unmanned rocket called Ares 5 is intended to boost Orion capsules and lunar landers to the moon starting around 2020.

Earlier this month, the Obama administration set up an independent panel to review NASA's manned space flight options, including Constellation and alternative architectures.

Leckrone said he worried that the Constellation program, facing tight budgets and demanding technical challenges, is "just plowing ahead, producing what they're able to produce within all the constraints."

"And my question is, OK, once you've produced it what do you do with it?" Leckrone said. "This is the way to keep human spaceflight alive, but what are the people going to be doing, except going back and forth to the space station? Which is a wonderful thing to do, and I hope the space station becomes extraordinarily, scientifically productive, but it is not today."

He said if the Constellation program "doesn't begin talking to their potential customer base, they're going to end up with something that no one is interested in using."

Leckrone said Constellation managers have not sought input from the science community in the design of the new rockets like the shuttle program enjoyed during its initial development.

"I don't see any similar activity going on in the Constellation program, where they're actively engaging their potential user base to get requirements that should go into their basic design," Leckrone said. "End of story."


7:00 AM, 5/19/09, Update: Hubble Space Telescope released from shuttle Atlantis (UPDATED at 9:15 AM with deploy)

The repaired Hubble Space Telescope, boasting two new instruments, new gyros, fresh batteries, a new science computer. a refurbished star sensor and two instruments brought back to life by spacewalking astronauts, was released from the shuttle Atlantis today after a historic fifth and final orbital overhaul.

Astronaut Megan McArthur, operating the shuttle's 50-foot-long Canadian-built robot arm, released the 24,500-pound observatory at 8:57 a.m. as the shuttle sailed 350 miles above the west coast of Africa.

"And the release of the Hubble Space Telescope confirmed," said mission control commentator Kyle Herring. "Hubble now back on its own for the final time with a gentle release by one but carrying the fingerprints of hundreds of thousands."

NASA graphic showing orientation of Hubble and shuttle Atlantis
at the time of release (Photo: NASA TV)

As Atlantis pilot Gregory C. Johnson slowly backed Atlantis away, commander Scott "Scooter" Altman radioed mission control, confirming a smooth deploy.

"And Houston, Hubble has been released, it's safely back on its journey of exploration as we begin steps to conclude ours," Altman said. "Looking back on this mission, it's been an incredible journey for us as well. I think it's demonstrated the triumph that humans can have when they overcome challenges that are presented them.

"Not everything went as we planned, but we planned a way to work around everything and with the whole team pulling together ... we've been able to do some incredible things. And that's the thing that I think about Hubble, we've done it together. And now Hubble can continue on its own, exploring the cosmos and bringing it home to us as we head for home in a few days. Thank you."

"Houston copies, thanks for those words, Scooter," astronaut Dan Burbank replied from mission control. "Congratulations on a great series of spacewalks. It's wonderful to see Hubble, the most famous scientific instrument of all time, newly upgraded and ready for action, thanks to you."

Hubble's protective aperture door was opened a few minutes before deploy, at 8:33 a.m., allowing starlight to once again fall on its famously flawed 94.5-inch primary mirror. But engineers at the Space Telescope Science Institute in Baltimore and the Space Telescope Operations Control Center at NASA's Goddard Space Flight Center in Greenbelt, Md., will need most of the summer to test and calibrate Hubble's new and refurbished instruments and subsystems. If all goes well, the first pictures from the upgraded telescope will be released in early September.

For Atlantis' crew, flight controllers, Hubble scientists and engineers and uncounted fans of the space observatory around the world, release marked a bittersweet moment as the telescope receded into the dark of space, disappearing from view for the last time. With the shuttle program facing retirement after eight more space station assembly flights, no more Hubble visits are currently planned and no one will set eyes on the telescope again until a final mission, presumably robotic, sometime in the late teens or 2020s to drive it out of orbit.

"Certainly it's going to be for me, a very touching moment," astronomer-astronaut John Grunsfeld, making his third Hubble house call, said before launch. "When I first went to Hubble (in 1999), at the end of our three spacewalks, we deployed Hubble on Christmas Day, and I had very mixed feelings. I'd been working for a number of years on the Hubble project, had gone and done two spacewalks on that mission and felt like I'd just barely gotten to know the Hubble before we had to send it on its way. But it was a glorious Christmas present to everybody on planet Earth. It was a wonderful sight to watch it slowly drifting off on the Earth's horizon.

"I was privileged to go back again (in 2002) and I felt like I was visiting an old friend. I was convinced at the end of the last mission, as it floated away, that I would never get a chance to see the Hubble again but I knew somebody would. And of course that got thrown into disarray with the cancellation of the servicing mission on the shuttle, and so here I am, going back to visit an old friend, to give it a new life along with a team of some Hubble repeats, other Hubble huggers, and a new team.

"So I'm looking forward to that moment with some mixed emotions," he said. "But when we've successfully serviced the Hubble, with all of the things that we have on our plate, a very challenging mission and a very complex mission, when Hubble flies away I'm going to be very proud of the shuttle team that allowed us to go there and of the Hubble team that has come up with all of these fixes that will make Hubble just an incredible discovery machine."

Faced with certain doom in the wake of the 2003 Columbia disaster, when a final shuttle servicing flight was canceled because of safety concerns, Hubble won a new lease on life when former Administrator Mike Griffin reinstated Atlantis' mission after development of heat shield inspection and repair techniques.

Griffin said today he was "enormously gratified with the success of this mission, and the upgrading of Hubble to unprecedented capability."

"And I am incredibly proud of the NASA team that pulled it off," he told CBS News. "My hat is off to them."

Over the course of five back-to-back spacewalks, the Atlantis astronauts equipped Hubble with a powerful new $132 million camera, a new $88 million spectrograph, six new stabilizing gyroscopes, six fresh batteries, a refurbished fine guidance sensor and a new science data computer. The astronauts also pulled off two unprecedented repairs, bringing another camera and an imaging spectrograph back to life after failures in 2004 and 2007.

Hubble is now more scientifically powerful than at any point since launch in 1990 and with new gyros and batteries, it should remain operational for at least five more years and possibly more.

"I don't want to be provincial, but I truly believe this is a very important moment in human history and I think it's an important moment for science," said Hubble Project Scientist David Leckrone. "Just using what Hubble's already done as a starting point, it's unimaginable that we won't dramatically go further than that."

After Hubble's release, the astronauts faced a busy day of work inspecting the shuttle's reinforced carbon carbon nose cap, wing leading edge panels and heat shield tiles to make sure no damage has occurred from micrometeoroids or space debris since a similar inspection the day after launch.

The odds of a catastrophic impact from space debris are higher at Hubble's 350-mile-high altitude, on average about 1-in-229 compared to less than 1-in-300 for a typical space station flight at the lab's lower 220-mile-high altitude.

With Hubble safely on its way, Altman and pilot Gregory C. Johnson planed to carry out a rocket firing later this morning to lower one side of the shuttle's orbit to around 184 statute miles, reducing the risk of impact by about 15 percent.

Because Hubble operates in a different orbit from the International Space Station, the astronauts cannot seek "safe haven" aboard the lab complex if any major problems occur that might prevent a safe re-entry. As a result, the shuttle Endeavour is poised on pad 39B at the Kennedy Space Center, already prepped for an emergency rescue mission if any non-repairable problems are found.

But the kind of damage that might require a rescue mission is more likely during launch than it is from impacts with small, albeit dangerous, pieces of space debris. Today's heat shield inspection is designed to spot any such damage. With post-Columbia repair tools on board, mission managers are confident any relatively minor damage could be repaired without needing a rescue flight.

The heat shield passed its initial inspections after launch, although a sensor behind wing leading edge panel No. 11 on the ship's right wing recorded a presumed impact during the early hours of the mission. But the data indicate the event was below the damage threshold requiring repairs.

Assuming no problems are found today, the astronauts will enjoy a day off Wednesday before packing up Thursday for the trip home.

Along with lowering the odds of debris impacts, today's orbit adjustment also will make it possible to bring Atlantis home one orbit earlier than originally planned, giving the crew three shots at a Florida landing Friday and improving the odds of getting home ahead of potentially threatening weather. The first landing opportunity will come 10:01 a.m. Friday.

Here is a timeline of today's activity (in EDT and mission elapsed time; includes revision H of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05/19/09
03:26 AM...07...13...25...HST: SSR engineering playback
04:31 AM...07...14...30...Crew wakeup
06:01 AM...07...16...00...Group B computer powerup
06:16 AM...07...16...15...SRMS grapples HST
06:51 AM...07...16...50...HST power umbilical disconnect
07:11 AM...07...17...10...HST unberthing maneuver
07:36 AM...07...17...35...EVA prep
07:56 AM...07...17...55...HST release prep
08:11 AM...07...18...10...HST: Aperture door open
08:53 AM...07...18...52...HST release
08:54 AM...07...18...53...Separation burn No. 1
09:27 AM...07...19...26...Separation burn No. 2
09:51 AM...07...19...50...FSS stow
10:11 AM...07...20...10...Crew meals begin
11:02 AM...07...21...01...Orbit adjust rocket firing
11:11 AM...07...21...10...Group B computer powerdown
11:11 AM...07...21...10...SRMS unberths OBSS
12:51 PM...07...22...50...Starboard wing RCC survey
02:30 PM...08...00...29...Mission status briefing on NTV
02:31 PM...08...00...30...EVA tools stowed
02:41 PM...08...00...40...Nose cap survey
03:31 PM...08...01...30...Port wing RCC survey
05:46 PM...08...03...45...HST: 1st alignment
05:51 PM...08...03...50...OBSS ICC RCC survey
06:31 PM...08...04...30...LDRI downlinkn
08:31 PM...08...06...30...Crew sleep begins
09:00 PM...08...06...59...Daily highlights reel on NTV


2:17 PM, 5/18/09, Update: EVA No. 5 ends; Grunsfeld hails Hubble

Astronomer-astronaut John Grunsfeld, veteran of seven previous Hubble Space Telescope spacewalks and a self-described "Hubble hugger," inadvertently bumped into one of the observatory's two low-gain antennas toward the end of an otherwise smooth spacewalk today, knocking off a small end piece. Groaning with disbelief, Grunsfeld said, "oh, I feel terrible."

But engineers at the Goddard Space Flight Center quickly reported the antenna was still working normally. Grunsfeld and fellow spacewalker Andrew Feustel were asked to put a protective cover over the cone-shaped device for added insulation before ending today's spacewalk.

"Sorry, Mr. Hubble," Grunsfeld said as he headed back to Atlantis' airlock. "Have a good voyage."

"Consider it a goodbye kiss, John," someone said.

"Ah, thanks.

Dan Burbank in mission control tried to reassure Grunsfeld that he hadn't harmed the telescope.

"Just to let you know, we're feeling real good about this," he said. "We think that antenna's going to be just fine. Again, in receive mode it works just fine, expectation is it'll work great in transmit mode, too. There are a lot of happy folks down here on the ground, at Goddard, here at Johnson and all around the world. We just look back and kind of marvel at the last five days and all the amazing work, electronic brain surgery and I don't know how else you could put it that you guys accomplished on that telescope. Hubble's never had it better, it's never been more capable and it's just been a marvel to watch you guys do this.

"Thanks so much, Dan, I couldn't agree more," commander Scott Altman radioed from the shuttle's flight deck. "John, remember, take a moment here. This is it. The last spacewalk on Hubble and maybe our last visit to space. So enjoy this. You earned it."

"Thanks, I appreciate that. And Dan, thanks for those kind words. I hope we don't lose too many db (decibels). We really have achieved a lot out here. Thanks a lot, Scooter."

Helmet cam view showing white cover going back over
low-gain antenna (Photo: NASA TV)

Grunsfeld and Feustel began repressurizing the shuttle Atlantis' airlock at 2:22 p.m. to close out a seven-hour two-minute spacewalk, the crew's fifth and final EVA to service and upgrade the Hubble Space Telescope, 19 years after the observatory's launch.

With today's installation of a second battery pack, a refurbished fine guidance sensor and three insulation panels - one more than originally planned - the astronauts completed the last remaining objectives of NASA's fifth and final Hubble service call.

Before repressurizing the airlock, Grunsfeld, one of the space telescope's most ardent - and eloquent - supporters, took a moment to mark a "tour de force of tools and human ingenuity" and to thank the men and women who made Atlantis' mission possible.

"As Arthur C. Clarke says, the only way of finding the limits on the possible is by going beyond them into the impossible," he said. "And on this mission, we tried some things that many people said were impossible - fixing STIS, repairing ACS, achieving all the content that we have in this mission. But we've achieved that and we wish Hubble the very best.

"It's really a sign of the great country that we live in that we're able to do things like this on a marvelous spaceship like the space shuttle Atlantis. And I'm convinced that if we can solve problems like repairing Hubble, getting to space, doing the servicing we do traveling 17,500 miles an hour around the Earth, that we can achieve other great things, like solving our energy problems and our climate problems, all things that are in the middle of NASA's prime and core values.

"As Drew and I go into the airlock, I want to wish Hubble its own set of adventures, and with the new set of instruments we've installed, that it may unlock further mysteries of the universe."

The antenna incident occurred near the end of today's spacewalk as Grunsfeld was rigging Hubble's support platform for the telescope's deployment Tuesday.

"One last handshake with Mr. Hubble from me," Grunsfeld called at 2:27 p.m., removing a support post from the base of the telescope. "OK, I'm off the telescope."

"Copy, off the telescope," Mike Massimino said from the flight deck.

A few moments later, Grunsfeld apparently bumped the low-gain antenna.

"Low gain ant... hold, John, stop, stop, stop, stop, stop," Michael Good radioed from inside Atlantis as Grunsfeld floating near the base of the telescope.

"Thank you."

"OK. We liberated a small piece of something off the end of that."

"Yep, we did," someone said.

"You see where it went?"

"It's under the telescope, passing underneath," Good said. "OK, it's coming back down into the payload bay now."

"You see where?"

"Yeah, I can see it. It's right by the BAPS post. You can probably even get it."

"I don't think it's an issue," astronaut Michael Massimino said.

"Yep, I think we ought to get it," Grunsfeld disagreed.

"OK."

"We've got eyes on it," someone said.

"Let me go look at the antenna..." Grunsfeld said.

"It looks like a little piece of tape..."

"Ahhhh..." Grunsfeld groaned. "Is it a little piece of tape?"

"Yeah."

"I've got it," Feustel said.

"Oh no, I hope the antenna's OK," Grunsfeld said. "Oh, I feel terrible."

"You hit the low gain?" Massimino asked.

"I tapped the low gain antenna with my foot," Grunsfeld said. "Ahh...."

"There are two of them," Massimino said in an effort to cheer up his crewmate.

"No, Houston, do you have a picture of this?" Grunsfeld asked.

"Atlantis, Houston, we can't see you right now," Dan Burbank called from mission control.

"OK. I'm sick," Grunsfeld said. "It kind of knocked off the end cap."


2:10 PM, 5/18/09, Update: Astronauts install insulation panels, complete Hubble servicing

Astronaut John Grunsfeld removed tattered insulation from the Hubble Space Telescope today and installed cookie sheet-like panels in its place over three equipment bays to complete the final objectives of a five-spacewalk overhaul.

"That's about all the new equipment we have to install," astronaut Dan Burbank called from Houston. "You guys have done it all."

"A great effort all around," Atlantis skipper Scott Altman agreed. "You hear that guys? You've done it all."

"WE'VE done it all," Andrew Feustel corrected.

"Not yet, I'm still working," Grunsfeld said, attaching the final panel. "But it's been a great (achievement) up here."

Grunsfeld and Feustel retrieve replacement insulation panels
(Photo: NASA TV)

Atlantis launched with three sets of new outer blanket layer - NOBL - insulation, but only two were originally included in the crew's flight plan. The first panel, bound for equipment bay 8, was deleted from a spacewalk Sunday when the crew ran long completing an instrument repair.

Grunsfeld and Feustel started today's spacewalk nearly an hour early to allow time to get as much insulation work done as possible after installing a final set of batteries and a fine guidance sensor. As it turned out, the spacewalkers had no problems with the new equipment and they were able to install insulation over three of Hubble's equipment bays.

"John if you're done monkeying around with the telescope, I'll take you back to the airlock," astronaut Megan McArthur, operating Atlantis' robot arm, said around 1:45 p.m.

On the way, she paused and Grunsfeld could be seen holding a camera, taking a self-portrait with the Hubble Space Telescope in the background.

"This is a very beautiful spaceship," he said softly.

Grunsfeld, posing for a self portrait with Hubble in background
(Photo: NASA TV)

Feustel's view of Grunsfeld (Photo: NASA TV)

The new insulation panels clearly were needed. The flimsy insulation over bay 8 was tattered and flaking away after years in the extreme environment of space.

"OK, this one's going to be interesting," Grunsfeld said as he approached bay 8. "Ah, it's a mess. ... I'll peel off a corner and put a clip on the MLI (multi-layer insulation) where it's strong and then try to roll it up all together."

A few minutes later, carefully trying to remove the old insulation, Grunsfeld said "OK, I've lost one piece, it's floating towards the cabin away from the telescope."

"Yep, we can see it," someone said.

"OK, the clip's on there," Grunsfeld continued. It looks nice... Definitely floating towards, it'll go right overhead you guys. It's going to miss the solar arrays. A '2001: A Space Odyssey' thing. ... Bueno, I think it's going to be hopeless to try and preserve any of these patches. I'm going to go back to your plan, stuffing them in the bag."

"There's nothing left of them," someone said.

A few minutes later, another piece broke away.

"Another piece just went by my WVS (helmet cam), probably three by three, going out over the port wing," Feustel said.

"Yep, there goes the other big piece. Lost a big one..."

"Oh yeah," Megan McArthur said from the flight deck.

"A large piece coming forward..." someone said.

"It looks like it went over the solar array," Feustel said.


12:30 PM, 5/18/09, Update: Fine guidance sensor installed; astronauts press ahead with insulation panels

Astronauts John Grunsfeld and Andrew Feustel installed a refurbished fine guidance sensor in the Hubble Space Telescope today, completing the servicing mission's final major objective. Running ahead of scheduled, the spacewalkers now plan to install three insulation panels to replace degraded thermal protection on three of the observatory's equipment bays.

"All right, it's in. Nice work," Grunsfeld said as he slid fine guidance sensor No. 2 into its slow on the side of the space telescope.

"Very smooth, guys, that was beautiful," astronaut Mike Massimino said from Atlantis.

Grunsfeld pulls FGS-2 out of the Hubble Space Telescope
(Photo: NASA TV)

Feustel inspects the empty FGS-2 bay while Grunsfeld moves the
instrument to a temporary mounting point (Photo: NASA TV)

Grunsfeld initially was unable to loosen a latch holding the old FGS in place, trying one socket wrench torque setting and then another. Just as with installation of the new Wide Field Camera 3 last week, he applied a bit of additional elbow grease, and the latch popped free.

The swap-out was uneventful and after Grunsfeld connected electrical cables to hook the new unit up, engineers at the Goddard Space Flight Center in Greenbelt, Md., sent commands to verify electrical connectivity. The astronauts, meanwhile, closed a protective door over the new sensor and the old FGS was moved from a temporary mounting point to a transport container for return to Earth.

Atlantis passes above the Baja Peninsula (Photo: NASA TV)

Atlantis passes above Houston (Photo: NASA TV)

Running an hour ahead of schedule, the astronauts conferred with flight controllers and decided to press ahead with installation of three protective insulation panels, completing the full suite of planned Hubble upgrades.

"OK, Houston, I'm looking at it and I show it's just under three hours to a nominal timeline repress and we're thinking about how much of the NOBLs (new outer blanket layer insulation) we can get done," commander Scott Altman called to mission control.

"OK, yeah, that jibes with what we're showing as well," Dan Burbank replied from Houston. "First off, we had a good aliveness test on FGS-2R, just wanted to pass that along from the STOCC (Space Telescope Operations Control Center)."

"That's good news, appreciate that word so quick," Altman said. "Thanks to the STOCC for all that commanding and checkout. That helps us have confidence that what we're doing is working out."

"Well, we're so far ahead, and we're showing a good hour ahead on the flight plan, which is really our limiter today, your reward for doing so well is to install, we believe, all three NOBLs. LIke to get your input on that."

"And Houston, let me tag up with John and Drew," Altman said. "How do you feeling, John?"

"Gee, I don't know, Scooter," Grunsfeld joked.

"I had a feeling. How 'bout you, Drew, you all worn out from free floating?"

"I feel pretty good, actually," Feustel said. "I've got a lot more in me."

"OK, it looks like we're going to press," Altman said.


10:00 AM, 5/18/09, Update: Hubble battery replacement complete

Astronaut John Grunsfeld removed an aging battery pack from the Hubble Space Telescope today and installed a replacement. He had no problems and with today's work, combined with a battery module installation Friday, Hubble now has a full set of new nickel-hydrogen batteries.

John Grunsfeld, on the shuttle's robot arm, removes a battery
pack from the Hubble Space Telescope (Photo: NASA TV)

"All of battery 3R connectors are mated," Grunsfeld reported at 9:44 a.m. He then began closing the door to equipment bay 3 to complete the swap-out. A few minutes later, astronaut Dan Burbank in mission control reported a successful connectivity test.

"I'm happy to report a good aliveness test on the bay 3 battery," he said.

Grunsfeld helmet cam view of new battery pack
(Photo: NASA TV)

"Really nice work on batteries, guys," Michael Good radioed from Atlantis. "Aliveness test is good, as you heard, so we're on our way here today."

The next item on the agenda is installation of a refurbished fine guidance sensor.


8:30 AM, 5/18/09, Update: Spacewalk No. 5 begins

Running nearly an hour ahead of schedule, John Grunsfeld and Andrew Feustel switched their spacesuits to battery power at 8:20 a.m. to officially kick off the crew's fifth and final spacewalk to service the Hubble Space Telescope. The goals of today's excursion are installation of a second battery pack, a refurbished fine guidance sensor and insulation blankets to improve temperature control.

Andrew Feustal prepares for Hubble battery swap
(Photo: NASA TV)

"OK, Drew. Let's go and be productive," Grunsfeld quipped as the spacewalkers gathered tools and tethers and left Atlantis' cramped airlock.


07:30 AM, 5/18/09, Update: Astronauts prepare for final spacewalk

Running ahead of schedule, astronauts John Grunsfeld and Andrew Feustel are suiting up for the Atlantis crew's fifth and final spacewalk today, a six-hour excursion to equip the Hubble Space Telescope with a second three-battery power pack, a refurbished fine guidance sensor and fresh equipment bay insulation panels. One panel was deferred from a spacewalk Sunday when the crew ran out of time. Grunsfeld and Feustel plan to install it today if time is available.

Barring a future mission to drive Hubble safely out of orbit at the end of its life, this is the last time any astronauts will touch the space telescope and the end of today's spacewalk promises to be an emotional moment for Grunsfeld, an astronomer-astronaut and self-described "Hubble hugger" making his third visit to the iconic observatory.

In a news conference before launch, asked he he planned to "leave his mark" on Hubble, Grunsfeld said yes, "I think we all plan to leave our mark. And it's Wide Field Camera 3, it's Cosmic Origins Spectrograph, RSUs, batteries, fine guidance sensor." Then he joked that robot arm operator Megan McArthur "hopes to leave no marks at all on the telescope with the arm."

But given Grunsfeld's long history with Hubble, his role as NASA's chief scientist when he had to support former Administrator Sean O'Keefe's controversial decision to cancel this final servicing mission and his subsequent assignment to the crew when the flight was reinstated, NASA's most experienced Hubble astronaut almost certainly will have something memorable to say before returning to Atlantis' airlock.

Today's spacewalk is scheduled to begin around 9:16 a.m., although the crew was running well ahead of schedule and hoped to get out the door early. For identification, Grunsfeld, call sign EV-1, will be wearing a spacesuit with red stripes around the legs. Feustel, call sign EV-2, will be wearing an unmarked suit. In a reversal of roles from their earlier spacewalks, Grunsfeld will ride the shuttle's robot arm while Feustel will free float.

One of the top priorities of Atlantis' servicing mission was to install six fresh nickel-hydrogen batteries to replace a degraded set that has been in place since launch in 1990. The first three-battery power module was installed in equipment bay 2 during the crew's second spacewalk Friday.

Today, the final power module will be installed in bay 3. Feustel will prepare the new battery pack for removal from its transport container, removing 12 bolts holding it in place, while Grunsfeld, on the end of the shuttle's robot arm, opens the bay 3 door on Hubble and removes the old batteries, releasing 14 bolts and six electrical cables.

McArthur, operating the robot arm, will move Grunsfeld back down to the cargo bay to swap battery packs with Feustel, who will store the old set for return to Earth while Grunsfeld installs the new set on the telescope.

The next item on the agenda is installation of a refurbished fine guidance sensor, one of three that provides data to the telescope's computer system to help lock onto and track its astronomical targets.

"There are lots of ways that the pointing system on Hubble acquires targets, locks in on those targets, and then allows the science to be produced," Grunsfeld said in a NASA interview. "It has some eyeballs on the outside of the telescope, which are the fixed head star trackers, and they kind of give Hubble that 'Snoopy' look. They acquire the general orientation of the telescope just as the ancient mariners did by looking up at the sky as they were crossing the ocean.

"Once you get into the vicinity of where you want to look the fixed head star trackers' job is done and the fine guidance sensors take over. And what they do is they steal a little bit of light from the primary mirror. The light goes up from the primary mirror to the secondary and through a hole in the middle of the primary mirror, and the fine guidance sensors take that light, look at stars, identify them, lock onto them, and that's how the telescope points in the right place in the sky. And then the rate sensor units take care of all the little oscillations and disturbances. All these parts work together."

Grunsfeld and Feustel first will remove the old FGS 2, opening an access door, attaching a handling fixture, disconnecting electrical cables and attachment clamps and pulling the 900-pound unit out along its guide rails.

The old FGS will be temporarily mounted on an access platform along the left wall of the payload bay. The replacement FGS then will be removed from its transport container and moved to Hubble for installation. After bolting it in place and making the required electrical connections, Grunsfeld and Feustel will retrieve the old FGS and mount it in the transport container for return to Earth.

The flight plan originally called for installation of a new outer blanket layer - NOBL - insulation panel on equipment bay 8 Sunday, during the crew's fourth spacewalk, followed by a NOBL panel for bay 5 today. But the NOBL 8 panel was deferred Sunday when work to repair Hubble's Space Telescope Imaging Spectrograph ran longer than expected.

The spacewalkers hope to install both NOBLs today, on equipment bays 5 and 8, if time is available.

Grunsfeld described the NOBL panels as "big pizza sheets that we're going to put on the outside of the telescope where the insulation has become damaged and is peeling up and the stuff inside is either getting too hot or too cold. So we're going to fix those items."

Because this is the crew's fifth spacewalk in a row, flight controllers do not want it to run long because of concern about crew fatigue. Grunsfeld said Sunday, however, that the crew is in good shape and eager to complete the work.

Here is an updated timeline of today's activity (in EDT and mission elapsed time; includes revision F of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05:31 AM...06...15...30...Crew wakeup
06:46 AM...06...16...45...EVA-5: Preparations begin
08:16 AM...06...18...15...EVA-5: Spacesuit purge
08:26 AM...06...18...25...EVA-5: Spacesuit pre-breathe
09:06 AM...06...19...05...EVA-5: Airlock depressurization
09:16 AM...06...19...15...EVA-5: Spacesuits to battery power
09:21 AM...06...19...20...EVA-5: Airlock egress and setup
09:46 AM...06...19...45...EVA-5: Bay 3 battery R&R
11:06 AM...06...21...05...HST: Battery aliveness test
11:16 AM...06...21...15...EVA-5: FGS-2 replacement
12:41 PM...06...22...40...HST: FGS-2 aliveness test
01:16 PM...06...23...15...EVA-5: NOBL 5 (NOBL8 if time is available)
01:46 PM...06...23...45...EVA-5: Cleanup and airlock ingress
02:46 PM...07...00...45...HST high gain antenna deploy (1)
03:01 PM...07...01...00...EVA-5: Airlock repressurization
03:11 PM...07...00...10...Spacesuit servicing
03:21 PM...07...01...20...HST: Solar arrays slewed to 90 degrees
03:41 PM...07...01...40...HST: Battery functional test
04:00 PM...07...01...59...Mission status briefing on NTV
04:16 PM...07...02...15...LIOH and battery config
04:26 PM...07...02...25...Spacesuit swap
05:11 PM...07...03...10...HST high gain antenna deploy (2)
05:11 PM...07...03...10...Rendezvous tools checkout
05:56 PM...07...03...55...HST: FGS-2 functional test
06:16 PM...07...04...15...HD downlink opportunithy
08:31 PM...07...06...30...Crew sleep begins
08:45 PM...07...06...44...HST update on NTV
09:00 PM...07...06...59...Daily highlights reel on NTV
10:01 PM...07...08...00...HST: SSR engineering playback


5:50 PM, 5/17/09, Update: EVA No. 4 ends

Astronauts Michael Massimino and Michael Good began repressurizing the shuttle Atlantis' airlock at 5:47 p.m. to officially close out an eight-hour two-minute spacewalk. The total for the Atlantis astronauts through four spacewalks now stands at 29 hours and 54 minutes.


5:20 PM, 5/17/09, Update: Repaired spectrograph passes 'aliveness' test

Held up by a stripped screw, spacewalker Michael Massimino applied brute force muscle power to an otherwise delicate operation, breaking off an offending handrail and then carefully unscrewing more than 100 small fasteners to get inside a dead science instrument aboard the Hubble Space Telescope.

After pulling out a blown power supply circuit board, Massimino and crewmate Michael "Bueno" Good carefully installed a replacement card, closed the instrument up and began collecting tools and equipment while engineers at the Goddard Space Flight Center sent commands to verify electrical connectivity in a quick-look "aliveness" test.

"Atlantis, Houston, with a bit of news from the STOCC (Space Telescope Operations Control Center) if you're ready," astronaut Dan Burbank radioed around 5 p.m.

"We are definitely ready," astronomer-astronaut John Grunsfeld replied from Atlantis.

"We're all happy to report that STIS has come back with a good aliveness test."

Amid cheers from space, Massimino laughed and said, "that sounds great. Thanks so much, Dan."

Michael Good, on robot arm, wraps up extended spacewalk after
repairing the Space Telescope Imaging Spectrograph (Photo: NASA TV)

The goal of the operation was to restore one of two redundant channels in the Space Telescope Imaging Spectrograph, a state-of-the-art instrument that broke down in 2004 when its low-voltage power supply failed. A successful repair today would give Hubble scientists five operational instruments for the first time in the telescope's 19-year history.

During the first of the Atlantis astronauts' five planned spacewalks, the powerful new Wide Field Camera 3 was installed Thursday, along with a replacement science data computer. On Friday, six new stabilizing gyroscopes and three fresh nickel-hydrogen batteries were bolted in place. On Saturday, the new Cosmic Origins Spectrograph was installed and astronauts John Grunsfeld and Andrew Feustel successfully repaired the wide-field channel of the Advanced Camera for Surveys.

The ACS and the Space Telescope Imaging Spectrograph were not designed to be repaired in orbit and as such, they represented the greatest technical challenges for the crew. Going into the mission, engineers said they had more confidence in the maturity of the STIS repair plan and warned reporters that the ACS work was much more uncertain.

As it turned out, they were partly wrong and partly right. The ACS repair went much more smoothly than anyone expected and the astronauts successfully revived the heavily used wide-field channel. But they were unable to restore the camera's high-resolution channel to operation.

Conversely, the STIS repair ran into problems right from the start when a stripped screw prevented Massimino from removing a handrail as required before attempting to open the instrument's main electronics box. In the end, flight controllers opted for a brute-force approach, telling Massimino to simply pull the loose end of the handrail away until the stripped screw snapped off.

Running well behind schedule at that point, Massimino and Good then were stymied when a power tool's battery died, forcing the spacewalkers back to the shuttle Atlantis' airlock to retrieve a spare and to top off spacesuit oxygen supplies.

"Oh, for Pete's sake," Massimino muttered in frustration.

Finally, the astronauts installed a so-called fastener-capture plate and unscrewed 111 small fasteners, trapping the screws and washers between the electronics box cover and capture plates. The cover-capture plate combination then was pulled away, exposing the blown power supply card to view. Using a custom tool to avoid handing the fragile boards, Massimino and Good promptly swapped them out. The electronics box was sealed with a different cover plate, one requiring just two locking pins.

Massimino pulls a cover off, revealing circuit boards controlling the
Space Telescope Imaging Spectrograph (Photo: NASA TV)

Massimino's helmet cam shows the exposed STIS electronics box
(Photo: NASA TV)

With two operational cameras, two complementary spectrographs and a soon-to-be-reactivated infrared camera known as NICMOS, Hubble is more scientifically powerful now than at any time in its history.

But the astronauts are not yet done with this fifth and final servicing mission. During a final spacewalk Monday, Grunsfeld and Feustel plan to install a final three batteries and a refurbished fine guidance sensor, along with news insulation panels to strengthen areas weakened by Hubble's 19 years in the harsh environment of space.

Massimino and Good had planned to install one such panel today, but that task was deferred when the STIS repair ran long.

"Mass and Bueno, while you're closing the doors (I wanted to tell you) what a great job you did today and how proud we are of you," Atlantis commander Scott Altman called. "And also, I want you to take a look around because your spacewalk with Hubble is about to come to an end. We're bringing you in as soon as you close the doors."

"Thanks Scooter," Massimino replied. "The view is magnificent, it's great to work with the world going by and being out here with a good friend, Mike Good, is a pleasure."

"Those are good words, Mass," Good said. "It's really awesome to be out here. ... A lot of work, but well worth it."

Massimino summed up the spacewalkers' feelings, saying "it's a real privilege to get to see what we're seeing and get to work on this magnificent machine. I couldn't be any more grateful for the opportunity."


1:45 PM, 5/17/09, Update: Astronauts turn to plan C - muscle power - to free stuck bolt

Applying brute force to an interfering handrail locked in place by a stripped screw, astronaut Michael Massimino got a good grip, braced himself and pulled the top of the handrail away, shearing off the recalcitrant screw and clearing the way for a long awaited instrument repair on the Hubble Space Telescope.

It was the second time in the shuttle Atlantis' ongoing Hubble servicing mission that astronaut muscle power was called on to save the day. During the crew's first spacewalk Thursday, astronaut Andrew Feustel had to force a stuck bolt out with a socket wrench to release an old camera, making way for installation of the new Wide Field Camera 3.

During today's spacewalk, Massimino and Michael "Bueno" Good are attempting to repair the Space Telescope Imaging Spectrograph, a sophisticated instrument that suffered a major power failure in 2004. To repair the instrument, the astronauts must remove a cover plate held on by 111 small screws to gain access to a circuit board that must be replaced.

To get the cover plate off, they first had to remove a handrail preventing the attachment of an ingenious "fastener capture plate" designed to trap the small screws and washers as they are released. THe handrail was held in place by four screws. Three came out with no problem, but the fourth, in the bottom right position, refused to budge and the head was stripped by Massimino's power driver.

Despite multiple attempts and a different tool bit, the screw refused to budge. Flight controllers briefly considered attempting to remove smaller screws holding the base of the handrail in place, but they ultimately hit upon the brute force solution. With the top of the handrail free, controllers suggested Massimino simply pull it away until the lower screw snapped.

"Yeah, and Drew, before we get into it, just wanted to give you a little bit more information," astronaut Dan Burbank called from mission control. "This was just done, just now, at Goddard (Space Flight Center) on a flight equipment unit and it took 60 pounds linear (force) at the top of the handhold to fail the single bolt in the lower right position at the bottom."

"OK. Mass, you copy that?" Feustel asked. "Sixty pounds linear at the top of the handrail to pop off that bottom bolt. I think you've got that in you."

"I can try," Massimino agreed. "So what do we do? Just give us the steps."

With flight controllers laughing in the background at Massimino's eagerness, Burbank told the astronauts to stand by while engineers reviewed the plan and the techniques needed to capture any released debris. It was decided to use Kapton tape over the ends of the handrail to help trap any loose washers or debris.

"Just tell me what your hand placement plan is and what you think about managing the sharp edges after it breaks, if you want to try and rock it to fatigue it or just a straight pull?" shuttle commander Scott Altman radioed from the flight deck.

"I don't know. I think maybe rocking it a little bit and then pulling it off, you know, I can feel it now, starting to come away. I'm not going to have a big death grip on it, but do what I can to pull it off. Mike, you handy with the disposal bag? If we're lucky enough to break this thing?"

He then got a grip and prepared to pull the handrail away.

"Easy, easy, Mike, just real easy, OK?" Feustel said.

"Here we go," Massimino said, pulling the handrail away. There was no television coverage at the time, but he apparently had no problems.

"Mass, I didn't get a good look at it, but it looked like it all stayed intact with the tape."

"Yeah, it did, I don't think we scattered any debris," Massimino said.

"Don't touch that," Feustel said, apparently referring to the broken end of the handrail.

"No, I'm just pointing to it. You can see the bolt's still in there."

Even though the sheared screw was sticking up a bit from the surface of the instrument, flight controllers and the astronauts decided it was not a sharp-edge threat and that they could press ahead with the repair.

"Awesome job," Burbank said. "We agree, we're back in with the regularly scheduled programming. We understand we're a little bit more tether challenged than we were before and we really appreciate the additional description on the additional sharp edge concern. Wonderful."

Running nearly two hours behind schedule by that point, the battery in Massimino's power tool suddenly died, prompting an "oh, for Pete's sake!" from the frustrated spacewalker.

"How are you guys doing inside the spaceship?" he joked, calling his crewmates inside the shuttle Atlantis.

"It's a real nail biter, buddy," Feustel said dryly.

"I wonder how everybody's doing down in Houston?"

"We're having a great time down here as well," Burbank replied.


12:30 PM, 5/17/09, Update: Stripped bolt trips up Hubble instrument repair

Trying to remove a hand rail to clear the way for a long-awaited attempt to fix a failed spectrograph on the Hubble Space Telescope, astronaut Michael Massimino ran into a stubborn fastener and apparently stripped the head during repeated attempts to drive out the recalcitrant screw with a power tool. The bright yellow handrail must be removed to make room for attachment of a custom capture plate needed to safely remove 111 small non-captive screws holding an instrument cover plate in place.

The handrail's central bar is held in place by four screws. Three of those came out with no problem, but the fourth threw a wrench into the crew's plans. After re-tightening one of the loosened screws, Massimino made another attempt to free the stuck fastener.

Handrail with stripped fastener, from Massimino's
helmet cam (Photo: NASA TV)

"it looks like it's really galled up," Massimino said after repeated attempts to free the recalcitrant screw.

"It should still go in," Feustel said of the bit. "If it's opened up at all, you should still be able to push the bit in there."

"I can push the bit in, yeah. But it doesn't feel... maybe."

"We don't want to re-drive or re-attempt with this bit," astronaut Dan Burbank called from Houston. "So we're inclined to have you go to ATM 1 and get the spare yellow bit out of bit caddy 3."

"Can we just try it one more time and see if it'll get it? Before we do that?" Massimino asked.

"The risk is, Mass, if it has a chance at all and we strip it out, then we'll have no chance with a new bit."

"We copy and concur," Burbank agreed from mission control.

"Well, I think you might... all right," Massimino said. "I'm sorry, I don't know if we'll be able to get it. It just looks really stripped."

"Is this bit not looking too good, Mike?" Feustel asked.

"I think the bit is fine, it drove the other one back in."

"If the bit's got any material missing at all it just reduces the likelihood that it'll catch and grab that head," Feustel said. "Even in a degraded state, a new bit with fresh edges on it has a reasonable chance of grabbing onto the bolt head."

Burbank said flight controllers agreed it made sense to try with a fresh bit. Massimino then asked: "Do we have a plan if the new bit doesn't work? Can we try keeping the handrail on or something? Or... I don't know."

"We're looking at other options as well," Burbank said. "We still think a fresh bit with sharper edges might have a chance of biting. So that's still our inclination and we're working on plan C, I guess."

With crewmate Michael "Bueno" Good remaining in place on the end of the shuttle Atlantis' robot arm, Massimino made his way to a payload bay tool box and retrieved a bit caddy. He then swapped out the bits on his power tool and got in place for another attempt.

"OK, Mass, the key is don't wiggle the bit around, try to get it straight and keep it straight and nice, slow torque build up," Feustel advised.

"You probably need to push pretty hard to engage it as well, that'll help put a little extra friction on that," Burbank called.

Massimino tried again.

"It ain't turning," he said.

"So it's just spinning in the bit?" Feustel asked.

"Yeah. I'll try again. Mike, you want to get behind me? And I'll push as hard as I can again."

"And Mass, for this time, try to see if you can see the hex alignment, try to get it lined up and push before you pull," Feustel said. "It may be only the outer portion of the hex is worn away and the inner portion is still partially intact."

"I'm trying, Drew. Lemme see... I'm trying all those things. Let's try again. Ready Mike?"

"Yep."

Straining to push the drill bit into the Torx head, Massimino grunted as he tried to force the bit in hard enough to engage. But the bolt refused to budge.

"What was plan C?" Massimino asked.

The astronauts then began collecting tools for an attempt to remove bolts at the base of the handrail stanchions in a bit to work around the problem.


9:50 AM, 5/17/09, Update: EVA No. 4 begins

Astronauts Michael Massimino and Michael Good switched their spacesuits to internal battery power at 9:45 a.m. to officially kick off a planned six-and-a-half-hour spacewalk, the fourth of five planned for the crew's Hubble Space Telescope servicing mission.

The Hubble Space Telescope over the coast of Africa early Sunday
(Photo: NASA TV)

After a half hour of work to set up tools, safety tethers and foot restraints, the spacewalkers will begin an attempt to repair the Space Telescope Imaging Spectrograph, an instrument that broke down in 2004.


7:30 AM, 5/17/09, Update: Astronauts prep for fourth spacewalk

Pressing ahead with a complex overhaul of the Hubble Space Telescope, astronauts Michael Massimino and Michael "Bueno" Good are gearing up for a planned six-and-a-half-hour spacewalk to install insulation and repair a sophisticated spectrograph that broke down in 2004, the victim of a blown power supply.

To fix it, Massimino will have to unscrew more than 100 small, non-captive fasteners, trapping them in an ingenious "fastener-capture plate" designed to retain the screws and washers holding a cover plate in place.

In some ways similar to an attempt to repair the Advanced Camera for Surveys during a spacewalk Saturday, Massimino and Good must open up an instrument that wasn't designed to be serviced in orbit - the Space Telescope Imaging Spectrograph - and replace a circuit board, installing a new power supply in the process.

But unlike the ACS repair, which was devised on short notice and which included somewhat experimental steps to "back power" one camera channel through the electronics of another, the STIS repair is considered more mature and straight forward.

Hubble Program Manager Preston Burch said before launch the odds of a successful repair were "better than 50-50 for ACS and I think they're much better than 80 percent for STIS."

As it turned out, the ACS repair was only partially successful but it accomplished the science team's primary objective. The more heavily used wide-field channel appears to be working again - a major success for the Hubble team - as is the so-called solar blind channel. But tests indicate the camera's high-resolution channel still has problems with its power system.

"The folks had a chance to analyze the data that was dumped during the night," astronaut Dan Burbank told the crew from Houston early Sunday. "I'm happy to report that although the high-res channel is still not functional, the wide-field camera, which is the real workhorse, carrying around 95 percent of ACS's science output, appears to be fully functional now. Nice job."

"Thanks very much, I really appreciate that," replied John Grunsfeld, who carried out the ACS repair Saturday. "Great job to everybody on the team who worked that."

"And just so you know, we also ran a functional test on the solar blind (channel)," Burbank continued. "We didn't expect any issues there and as expected, it's fully functional as well."

"Fantastic! Power is restored to ACS," Grunsfeld said.

Engineers have higher confidence Massimino and Good can restore STIS to operation.

"Over the past two-and-a-half years leading up to this flight, we've kind of ironed out little changes in how we want to do things and practiced over and over again," Massimino said in a NASA interview. "For STIS, we have a bit of an advantage in that we have an actual trainer that they built for us. It's a little mockup of the area we're going to be working in and we've spent a lot of time together, all of us, inside of that trainer.

"There are a lot of steps and a lot of things that can go wrong during that procedure. But together, all of us working as a team and practicing, practicing, practicing, we're whittling that down. We feel pretty confident we're going to be able to do this task and pull it off and get the electronics board replaced. But it's going to be very challenging and a real interesting task."

Today's spacewalk is scheduled to get underway around 9:16 a.m. Massimino, call sign EV-3, will be wearing a suit with broken horizontal stripes around the legs. Good, call sign EV-4, will be wearing a suit with barber pole stripes.

This will be the fourth of five planned EVAs for othe Atlantis astronauts and the 22nd spacewalk devoted to Hubble servicing. The Atlantis astronauts have logged 21 hours and 52 minutes of EVA time during their three previous spacewalks while total Hubble EVA time now stands at 151 hours and two minutes.

The STIS repair is the first item on today's agenda and it will take up most of the crew's time. Massimino will be the designated "free floater" while Good will be anchored to the end of the shuttle's robot arm. Massimino is responsible for the bulk of the STIS repair.

STIS broke down in August 2004. To fix it, Massimino must remove a handrail, a cover held by 111 screws and then replace a circuit board that is locked in place.

"In order to get at a failed electronics board inside the STIS main electronics box, we need to take the cover off the box," Burch said. "We're very fortunate in that when the astronauts open the doors to the aft shroud and look at this instrument, that cover is sitting right there in front of them. The challenge is the 111 screws that are holding it on. The screws are not captive. So they have to go in there and take all these screws out. You can imagine what went through a lot of people's minds when we first started thinking about this, you know, 111 screws floating around all inside Hubble. That was unacceptable.

"So, we came up with a very clever device called the fastener capture plate, which is basically made out of a Lexan-type material. This plate goes over the top of the MEB (main electronics box) cover, it's aligned and fastened on there. And then this fastener capture plate has a series of little holes in it that line up with all the screws. The holes are small enough to allow the tool bit to go in so you can turn the screw, but they're small enough to keep the screw from falling out. So once you get all 111 screws taken care of, the cover stays attached to the fastener capture plate and you move the whole thing out. So all the debris and all the screws are captured in there."

An astronaut-friendly replacement cover was developed that will be installed in place of the main electronics box cover that was removed.

"Once we're done servicing, we take the new cover and put it on," Burch said. "There are two latches, you just throw the latches and bingo, it's on there. And then there's a third latch they throw that has some fingers that grab the electronics boards and mate them to the cover."

That was one challenge. Another was making sure the astronauts could replace the circuit card with the failed power supply.

"If you've ever fooled around with your desktop computer, those things usually aren't much of a challenge," Burch said. "But the way these instruments are built on Hubble, these boards slide into slots in the box but they're held in place by things called wedge locks. And the wedge locks are designed to keep the boards from rattling around and they also provide a heat path to reject waste heat out to the sides of the box so things stay nice and cool.

"Unfortunately, these wedge locks have a property like these Chinese finger handcuffs you may have played with as a kid. You put them on and the harder you pull, the tighter it gets. Well, the wedge locks have this kind of a property and when you loosen the bolts on them sometimes you can slide the board right out and sometimes you have to wrestle with it for a half hour or an hour to get it out.

"We obviously needed a tool to overcome this problem. So we have a card extraction tool that was developed. We went into a small research program to see even if these wedge locks jammed in their worst possible way could we pull the board out without having the board disintegrate and leave a pile of debris. I'm happy to report we've come up with a tool that enables us to do exactly that. So those were the major challenges."

The card extraction technique was successfully demonstrated during the ACS repair Saturday using a slightly different tool.

Here is an updated timeline of today's activity (in EDT and mission elapsed time; includes revision E of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05/17/09
03:31 AM...05...13...30...HST: SSR engineering playback
05:31 AM...05...15...30...Crew wakeup
06:46 AM...05...16...45...EVA-4: Preparations begin
08:16 AM...05...18...15...EVA-4: Spacesuit purge
08:26 AM...05...18...25...EVA-4: Spacesuit pre-breathe
09:06 AM...05...19...05...EVA-4: Airlock depressurization
09:16 AM...05...19...15...EVA-4: Spacesuits to battery power
09:21 AM...05...19...20...EVA-4: Airlock egress and setup
09:46 AM...05...19...45...EVA-4: STIS repair
01:26 PM...05...23...25...HST: STIS aliveness test
01:56 PM...05...23...55...HST: STIS functional test
02:16 PM...06...00...15...EVA-4: NOBL 8
03:01 PM...06...01...00...EVA-4: Cleanup and airlock ingress
03:46 PM...06...01...45...EVA-4: Airlock repressurization
03:56 PM...06...01...55...Spacesuit servicing
04:45 PM...06...02...44...Mission status briefing on NTV
05:01 PM...06...03...00...LIOH and battery config
05:01 PM...06...03...00...EVA-5: Tool config
05:21 PM...06...03...20...Spacesuit swap
06:01 PM...06...04...00...HD downlink opportunity
06:16 PM...06...04...15...EVA-5: Procedures review
09:31 PM...06...07...30...Crew sleep begins
09:45 PM...06...07...44...HST update on NTV
10:00 PM...06...07...44...Daily highlights reel on NTV
11:01 PM...06...09...00...HST: SSR engineering playback
12:31 AM...06...10...30...HST: Bay 3 battery discharge


9:50 PM, 5/16/09, Update: Engineers evaluating data from ACS wide-field camera functional test; run into power problem with high-resolution channel UPDATED at 6 a.m.; high-resolution channel 'down for the count;' wide-field channel appears to be working normally)

A functional test of the Hubble Space Telescope's Advanced Camera for Surveys, overhauled during a spacewalk Saturday by astronauts John Grunsfeld and Andrew Feustel, indicates success reviving the instrument's heavily used wide-field channel, officials said early Sunday. But testing shows the overhaul failed to resolve power problems with the camera's stricken high-resolution channel and it appears "down for the count."

The ACS, a sophisticated camera installed during a shuttle servicing mission in 2002, was designed to operate in three modes: a high-resolution channel, a wide-field camera and a so-called solar blind channel. Following major power system failures in 2006 and 2007, the heavily used wide-field and high-resolution channels were knocked out of action. The solar-blind channel later was restored to operation.

During Saturday's spacewalk, Grunsfeld replaced four circuit boards in the wide-field channel electronics and attached a replacement low-voltage power supply. Engineers devised a way to "back-power" the high-resolution channel with the new power supply and control electronics, although they were less confident of that plan's success.

The ACS passed an initial aliveness test during the spacewalk and engineers at the Goddard Space Flight Center in Greenbelt, Md., began a more detailed functional test later in the evening. An early step in that procedure turned on the high-resolution channel and almost immediately engineers saw it drawing too much current. The test was halted and commands to the high-resolution channel were taken out. Testing of the wide-field channel later resumed.

"The wide field channel was tested this evening, that was the major focus of the spacewalk yesterday, trying to get that channel back up and running," mission control commentator Josh Byerly said early Sunday. "The payloads officer confirmed that everything looks fine on the wide-field channel. So good news on that front.

"The high-resolution channel, however, ran into some issues, some power fluctuations were seen. ... They did confirm the short in the wiring of the high-resolution channel was actually upstream of where the astronauts were working yesterday. What this means is the repair was not successful on that specific channel."

The wide-field channel is the most heavily used by the science community and as a result, the repair work Saturday is "still considered a success, even with this high-resolution channel being down for the count," Byerly said.

In an interview before launch, Hubble Program Manager Preston Burch described the complexity - and the unknowns - associated with repairing the ACS high-resolution channel.

"It turns out there are shared copper paths between the electronics for both of those channels," he said. "So what we said was, hey, why don't we get to the high-res channel through the electronics paths that are connected to the wide-field channel? We'll just back power the existing printed circuit boards that are in the high-resolution channel CCD.

"We tested that on the ground and sure enough, it turns out to be feasible to do that. The only question mark is the status of the low voltage power supply on the MED 1 and MED 2 sides. In other words, it's possible that if there's damage on the sides of the interpoint converters, the secondary sides that are powering the high-resolution channel, it's possible there are some short circuits there that will prevent this scheme from working. Particularly on the one side that suffered the major damage. That may not work very well."

During the spacewalk Saturday, Grunsfeld installed a new low-voltage power supply "that will try to rejuvenate, or bring back to life, the high-resolution channel by back powering the high-res channel through these shared copper paths that connect to the wide-field channel," Burch said. "I won't say it's a long shot. It IS somewhat of a long shot, but people need to understand that this doesn't have the same degree of rigor as, let's say, building a brand new science instrument or a new black box that we're hooking up to standard interfaces that already exist on the telescope. This is really a bit of an experiment."


04:20 PM, 5/16/09, Update: Grunsfeld pulls off tricky camera repair (UPDATED at 6:10 p.m. with quotes from program manager)

In what amounted to electronic brain surgery, a spacesuited astronaut cut through shielding on a broken camera deep inside the Hubble Space Telescope today, removed a cover plate that wasn't designed to be taken off in orbit, used a custom tool to pull out four blown circuit boards and then installed a fresh set.

Running up to an hour ahead of schedule at one point, astronomer-astronaut John Grunsfeld, a self-described "Hubble hugger" making his third visit to the telescope, then spliced in an electrical cable and connected it to a new low-voltage power supply that replaced one destroyed in 2007 by a catastrophic short circuit.

The improbable repair job went smoothly, with virtually no problems of any significance, and by 2:56 p.m., the final connections had been made, catching ground engineers by surprise.

"All connectors are mated," astronaut Michael Good radioed from Atlantis.

"Houston copies. Again, great work on that," astronaut Dan Burbank replied from mission control. "We've got to modify our aliveness test. It may take a little bit longer, didn't expect to be this far along."

"Well that's good news, thanks Houston."

John Grunsfeld pulls a circuit board from the Advanced
Camera for Surveys (Photo: NASA TV)

Grunsfeld and crewmate Andrew Feustel then gathered their tools and equipment while engineers at the Goddard Space Flight Center in Greenbelt, Md., sent commands to verify the sophisticated instrument's three camera channels were properly connected.

Mission control commentator Pat Ryan reported at 3:22 p.m. that the Advanced Camera for Surveys had, in fact, passed its initial aliveness test. The crew was informed at 3:51 p.m.

"Atlantis, Houston, for EVA. We have a good aliveness test on ACS," Burbank radioed.

"Woo hoo!" someone exclaimed from orbit.

"Ah, that's unbelievable!" Grunsfeld said.

"It's believable," someone said.

"I'm hoping one and a half electrons are left," Grunsfeld joked.

"Nice work, guys," Atlantis commander Scott Altman radioed. "Congratulations to you John, and Drew, for a great effort. I know it was made possible by all the folks who really put a plan together in record time to save ACS. So our thanks to them as well."

"Great words, Scooter," Grunsfeld agreed.

A more detailed functional test will be carried out this evening, starting around 7 p.m., to determine the camera's overall health.

Going into the unprecedented repair, only one of the advanced camera's channels, the so-called solar blind camera, was still functioning. Assuming the new circuitry performs as expected, engineers hope to revive the camera's heavily used wide-field channel and, with luck, it's powerful high-resolution channel.

Coupled with the successful installation of the $88 million Cosmic Origins Spectroscope earlier today, Grunsfeld and Feustel chalked up a flawless spacewalk, accomplishing two of the crew's major objectives.

"I thought today's EVA was just absolutely amazing," said Hubble Program Manager Preston Burch. "We struggled a little bit here the first day or two and we didn't really quite know how it was going to play out today. Because you just never know. ... John Grunsfeld and Drew Feustel just made it look so easy out there. It was just absolutely amazing."

The six-hour 36-minute spacewalk ended at 4:11 p.m., within a few minutes of the targeted time, when Grunsfeld and Feustel began repressurizing Atlantis' airlock. Today's EVA, the third of five planned by the Atlantis astronauts, pushed the crew's total to 21 hours and 52 minutes. Total Hubble EVA time in 21 spacewalks over four servicing missions stands at 151 hours and two minutes. Grunsfeld now ranks fourth on the list of most experienced spacewalkers, with 51 hours and 28 minutes of EVA time during seven Hubble spacewalks over three missions.

The day's work began with removal of the no-longer-needed COSTAR corrective optics package and installation of the Cosmic Origins Spectrograph, a swap out that took about two-and-a-half hours to complete and came off without a hitch.

After COS was installed, Feustel, mounted on the end of the shuttle Atlantis' robot arm, carried the 800-pound COSTAR to the same storage box used to carry the new spectrograph into orbit.

"Just an unbelievable view," Grunsfeld radioed his crewmate. "I've got you and COSTAR, riding the arm, the Earth's limb in view, the curvature of the beautiful blue Earth and a half moon setting."

"Take a picture, John," someone said.

"We are."

Feustel moves COSTAR toward its storage container (Photo: NASA TV)

A few minutes later, ground controllers reported a successful COS aliveness test, indicating the new instruments was properly plugged into Hubble's power and data management system.

"Drew and John, excellent job getting COS inside and COSTAR out and safe to come home," astronaut Michael Massimino radioed from Atlantis' flight deck.

"I just want to add a special congratulations to ... all the folks at the University of Colorado-Boulder and Ball Aerospace for getting COS up here after all these many years," Grunsfeld said.

The ACS repair work began a few minutes past 1 p.m. Working inside the cramped confines of a Hubble instrument bay, Grunsfeld used a custom grid cutter tool to remove electromagnetic shielding from the phone booth-size camera and then removed six of the Torx fasteners securing a cover plate.

"Number one is out, Bueno," Grunsfeld radioed crewmate Michael "Bueno" Good. "Yay!" A moment later, he added: "I don't think brain surgeons go 'yoo hoo' when they pull something out."

After screwing in mounting posts, he attached a clear plastic "fastener-capture plate" designed to trap the small, non-captive screws holding the cover plate in position.

"This activity is dedicated to studying the behavior of tiny screws in space," Grunsfeld joked. "All the screws are out, Bueno."

Grunsfeld exposes ACS circuit boards to view (Photo: NASA TV)

Grunsfeld then used a power screw driver to remove the 26 remaining Torx-head fasteners and pulled the cover plate, and the trapped free-floating screws, off to expose four critical circuit boards. Using a custom tool, he extracted the cards one at a time with no problem and replaced them with a box containing four new cards.

"Those cards look new," Grunsfeld said.

"Not like the ones we've been abusing for a couple of years (in training)," Feustel joked.

The final step in the repair job was to wire in a new low-voltage power supply designed to power the high-resolution and wide-field channels of the camera.

"So now we're 60 percent of the way through this servicing mission, we've accomplished five and a half of our top six priorities, the other half being the installation of the other battery module and that won't happen until (Monday)," Burch said.

"But at this point we're felling really good. I think you can say at this point in time, Hubble has reached a new high in terms of its capability with what we have today. We've also made huge strides in terms of restoring the health of the observatory and the next couple of days, we expect to finish up the rest of the work we have planned."

During a news briefing Friday, Hubble Project Scientist Dave Leckrone made a Joe Namath-style bet on the outcome of today's spacewalk.

"I have a prediction," he said. "We've always said EVA 3 was going to be the most difficult and the most challenging, and I predict it's going to go more smoothly than any other EVA on this mission. I just think that's some version of Murphy's Law that's going to lead us in that direction."

He was right.


12:15 PM, 5/16/09, Update: End of one era, start of another: Cosmic Origins Spectrograph replaces COSTAR in Hubble Space Telescope

Marking the end of an era, spacewalkers Andrew Feustel and John Grunsfeld removed the no-longer-needed COSTAR corrective optics package from the Hubble Space Telescope today and replaced it with the Cosmic Origins Spectrograph, an $88 million state-of-the-art instrument designed to study the large-scale structure of the universe.

The $50 million COSTAR, or Corrective Optics Space Telescope Axial Replacement, was installed in 1993 during the first Hubble servicing mission. It was equipped with small mirrors that exactly counteracted the spherical aberration marring Hubble's famously flawed primary mirror. COSTAR routed corrected light to all of Hubble's instruments except the Wide Field Planetary Camera 2, which had its own built-in corrective optics.

Andrew Feustel, on the shuttle Atlantis' robot arm, moves the COSTAR
off to one side of the Hubble Space Telescope (Photo: NASA TV)

"This is really pretty historic, pulling out the COSTAR," astronomer-astronaut Grunsfeld noted as the spacewalkers prepared to remove the boxy 800-pound instrument.

With COSTAR temporarily stowed on a fixture mounted on the left side of Atlantis' payload bay, Feustel and Grunsfeld opened the Cosmic Origins Spectrograph storage box, disconnected a ground strap and released bolts holding it in place. Then Megan McArthur, operating the robot arm from inside Atlantis, moved Feustel and the new instrument back to the space telescope.

"Beautiful instrument," Feustel observed.

Holding COS vertical, Feustel and McArthur, with guidance from Grunsfeld, carefully moved COS into position to engage the same guide rails that held COSTAR in place. The astronauts had no problem sliding COS into place, locking it down and connecting electrical cables to complete the installation just past noon.

"Great job, excellent. COS is in there," Michael Massimino said from Atlantis' flight deck after Grunsfeld drove in a latch bolt. "Nice work, boys."

Working in orbital darkness, Feustel (left) and Grunsfeld install COS
(Photo: NASA TV)

"The Cosmic Origins Spectrograph is a physics machine," Grunsfeld said in a NASA interview. "Whereas the Wide Field Camera is taking images which contain a lot of physics and a lot of information, the spectrograph takes the light that's coming from an object and breaks it up into tiny little bins by frequency and allows us to see spectral lines that are caused by oscillations of, of electrons and atoms, transitions between states, and from that you can tell the temperature, the density, all kinds of important details of what's going on, say, in a stellar atmosphere or in the gas between stars.

"And in particular, the Cosmic Origins Spectrograph is going to investigate the space between stars in our own galaxy, interstellar medium, and even more important, the space between galaxies in the universe. When the universe was made, just like when you build a house, there was a lot of stuff left over, and the shape of that stuff is a critical factor in determining what the nature of the universe is, and in particular subjects like dark matter.

"Because normal matter, the stuff we're made out of, hydrogen gas, helium gas, all the atomic elements, will clump around this dark matter that has the same effect of gravity as regular matter but doesn't interact the way normal matter does with light, so we can't see it. And it turns out the structure of the universe is dominated by this dark matter. The Cosmic Origins Spectrograph will be able to look through the universe and, using this physics tool, help us understand what the universe is made of and, and how it was formed."


9:35 AM, 5/16/09, Update: Spacewalk No. 3 begins

Astronauts John Grunsfeld and Andrew Feustel, floating in the shuttle Atlantis' airlock, switched their spacesuits to internal battery power at 9:35 a.m. to officially begin a planned six-and-a-half-hour spacewalk.

The first item on the agenda is to remove a no-longer-needed corrective optics package called COSTAR from the Hubble Space Telescope and to replace it with the new Cosmic Origins Spectrograph. That work will take most of the morning, with a spectrograph "aliveness" test on tap just before noon.

If all goes well, Grunsfeld and Feustel then will begin the most challenging portion of the spacewalk, attempting to repair the Advanced Camera for Surveys, which suffered a catastrophic power system failure in early 2007.

Today's spacewalk, the third of five planned for the Atlantis astronauts, is scheduled for six-and-a-half hours, but flight controllers likely will extend it as needed to get the ACS repair completed.


7:50 AM, 5/16/09, Update: Grunsfeld, Feustel gear up for instrument installation, camera repair

Astronauts John Grunsfeld and Andrew Feustel are preparing for the most challenging - and uncertain - spacewalk of the crew's Hubble Space Telescope servicing mission: installation of a new spectrograph and the attempted repair of a broken camera that was not designed to be serviced in space.

The Advanced Camera for Surveys, or ACS, suffered multiple electrical failures in 2006 and 2007 that knocked two of its three cameras out of action. To fix them, Grunsfeld must install an external power supply and replace four circuit boards, The surgery, if successful, will re-route power through the instrument, reviving one of two command and data channels and restoring its ability to take wide-field and high-resolution photographs.

The complex job originally was spread out over two spacewalks. But the failure of a science data computer aboard Hubble last September, and the addition of a replacement to the Atlantis mission, forced flight planners to compress the ACS work into a single spacewalk.

"Basically, I have to cut an electromagnetic grid off that's kind of like a screen," Grunsfeld said before launch. "Then I have to remove No. 4 fasteners, these tiny little Torx-head screws. I have 32 of those, plus a few other screws, to remove a cover plate. Then I have to pull four circuit cards out and then we're going to replace that electronics with new electronics. Instead of putting cards back, we're just going to put a big box in and a new power supply. Our goal is to finish that, complete, in one EVA.

"The challenge for me, of course, is ... the location of the electronics box on the ACS is not right in front of me, but it's sort of around a corner. So I'm kind of working as if I'm underneath a car trying to remove some screws that I can't see. And some of the screws, in fact, I can't see, I have to go by feel with a little manual screwdriver. We've practiced this over and over again in the (water) tank. ... We've tried to make this feel routine. But I would say ... this repair is different from previous repairs I've done on Hubble, (it) has not yet become routine. I think this is going to be a nail biter all the way up until we actually do the repair."

Because the crew's second spacewalk, by Michael Massimino and Michael Good, ran long Friday, the crew was given an extra hour to unwind Friday night and wakeup today was delayed an hour. As a result, Grunsfeld and Feustel plan to begin today's spacewalk one hour later than originally planned, around 9:16 a.m.

This will be the 21st spacewalk devoted to Hubble servicing over four missions, the third of five planned for the Atlantis astronauts, the seventh overall for Grunsfeld and the second for Feustel. Going into today's excursion, 16 astronauts had logged 144 hours and 26 minutes of Hubble spacewalk time, including 15 hours and 16 minutes during spacewalks Thursday and Friday.

Grunsfeld currently is eighth on the list of most experienced spacewalkers with 44 horus and 52 minutes of EVA time. With today's spacewalk, he is expected to move up to No. 4, behind cosmonaut Anatoly Solovyev and astronauts Mike Lopez-Alegria and Jerry Ross.

For identification purposes, Grunsfeld, call sign EV-1, will be wearing a suit with red stripes on the legs while Feustel, EV-2, will be wearing a suit with no stripes.

The first item on the agenda after exiting the airlock and setting up tools and tethers is to remove the COSTAR instrument from Hubble to make way for the new Cosmic Origins Spectrograph. COSTAR, the Corrective Optics Space Telescope Axial Replacement, was installed in 1993 during the first Hubble servicing mission. It was equipped with small mirrors that were ground to a shape that exactly counteracted the spherical aberration marring Hubble's primary mirror. COSTAR routed corrected light to all of Hubble's instruments except the Wide Field Planetary Camera 2, which had its own built-in corrective optics.

Grunsfeld and Feustel will remove COSTAR and temporarily mount it on the side of the shuttle's cargo bay. After pulling the Cosmic Origins Spectrograph from its storage container, the astronauts will slide it into COSTAR's place in the Hubble Space Telescope. COSTAR then will be stored to the spectrograph's payload bay container for return to Earth.

"We haven't said a lot about COS and it's sort of the quiet instrument back in the background waiting to come out and be a super star," said Hubble Project Scientist David Leckrone. "COS is the most sensitive spectrograph ever to fly in space. A spectrograph is kind of a poor relative to a camera, it doesn't take pretty pictures, it merely produces precise, quantitative astrophysical data on everything in the sky that we point it to: What is something made of, how hot is is, how dense is it, how fast is it moving through space, etc."

Unlike Hubble's broken Space Telescope Imaging Spectrograph, which Massimino and Good will attempt to repair Sunday, "COS is focusing particularly on ultraviolet wavelengths whereas STIS, which we hope to get repaired, can go all the way up into the visible. COS is a medium-resolution spectrograph, STIS is a high-resolution spectrograph. STIS can take imaging spectra, two dimensional spectra of an exteneded object like a nebula, COS is a point source spectrograph. So they're quite different and they're very complementary to each other.

"But COS is very much more sensitive than STIS in the ultraviolet," Leckrone said. "So it wants to go as deep out in space, as far back in time as it can, as fast as it can."

With COS in place, the astronauts will turn their attention to the Advanced Camera for Surveys, which is located in the same equipment bay.

Grunsfeld, anchored to a foot restraint on the telescope, first must cut away the camera's electromagnetic shielding using a special tool called a grid cutter. He then will remove a cover plate held in place by 32 non-captive fasteners. To make sure the screws don't float away, Grunsfeld will attach a fastener capture fixture over the cover plate that will trap the fasteners as they are backed out. Then he can remove the capture device and cover plate as one piece, exposing the camera's internal electronics.

Using a circuit card extraction tool, Grunsfeld will pull out four blown circuit boards. He then will attach a new set of cards in their own carrier, bypassing the camera's original equipment. A new low-voltage power supply also will be wired into the ACS system to complete the repair.

"I have high confidence going into it that we'll be able to finish it in one EVA day, maybe a slightly extended EVA day, but that's in the absence of any surprises," Grunsfeld told CBS News before launch. "And one thing I've learned from the first two missions and involvement in all the Hubble missions is, Hubble is always full of surprises. So we'll have to see on the day we get there."

For minimum mission success, the astronauts must successfully repair at least one of the broken instruments. If the ACS repair is not successful but the STIS repair is, NASA will not add any additional ACS repair work to the crew's fifth and final spacewalk Monday. If the STIS repair is not successful, however, installation of a refurbished fine guidance sensor Monday will be deleted and the astronauts will continue with whichever repair job shows the most promise of success.

"It's important to understand that achieving success in restoring the operation of STIS and ACS is much less certain than the other activities we will be performing on SM-4," said Preston Burch, Hubble program manager at NASA's Goddard Space Flight Center. "The problems were diagnosed on the ground. Normally, if you're going to repair electronics, you like to take the electronics box into a shop where you have a lot of test equipment and parts and personnel who can work on it in a shirt sleeves-type environment.

"We don't have the luxury of doing that. What we are using here are basically clues that we have received from the telemetry to solve a puzzle. I think this is sort of similar to these crime scene investigation shows that are so popular on TV. I like to refer to Goddard as 'CSI: Goddard' when we start getting into the forensics of trying to figure out what has caused a piece of equipment to fail.

"There are uncertainties in the knowledge of the cause of the particular failure. the electrical and mechanical interfaces or things we are not used to working on in space. We'll be using a lot of new tools and procedures for the first time and these tasks are very complex. Another important point is we'll only going to be able to repair one side of each of these instruments. In other words, the STIS instrument had a primary and a redundant electronics side. We've incurred failures in both of those sides. We only have time on this mission to repair one side on each of those instruments. So we will not be restoring full redundancy.

"We need to think about the repair of these instruments as really kind of an experiment, because this will be the first time we've attempted something like this and it's very challenging work," Burch said.

Here is an updated timeline of today's activity (in EDT and mission elapsed time; includes revision D of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05/16/09
03:26 AM...04...13...25...HST: SSR engineering playback
05:31 AM...04...15...30...Crew wakeup
06:46 AM...04...16...45...EVA-3: Preparations begin
08:16 AM...04...18...15...EVA-3: Spacesuit purge
08:26 AM...04...18...25...EVA-3: Spacesuit pre-breathe
09:06 AM...04...19...05...EVA-3: Airlock depressurization
09:16 AM...04...19...15...EVA-3: Spacesuits to battery power
09:21 AM...04...19...20...EVA-3: Airlock egress and setup
09:46 AM...04...19...45...EVA-3: Cosmic Origins Spectrograph
11:46 AM...04...21...45...HST: COS aliveness test
12:36 PM...04...22...35...EVA-3: ACS repair (part 1)
03:01 PM...05...01...00...EVA-3: Cleanup and airlock ingress
03:46 PM...05...01...45...EVA-3: Airlock repressurization
03:46 PM...05...01...45...HST: COS functional test
03:56 PM...05...01...55...Spacesuit servicing
04:45 PM...05...02...44...Mission status briefing on NTV
05:01 PM...05...03...00...EVA-4: Tools configured
05:01 PM...05...03...00...LIOH and battery config
05:21 PM...05...03...20...Spacesuit swap
06:16 PM...05...04...15...HD downlink opportunity
06:21 PM...05...04...20...EVA-4: Procedures review
09:31 PM...05...07...30...Crew sleep begins
09:45 PM...05...07...44...HST Update on NTV
10:00 PM...05...07...59...Daily highlights reel on NTV
11:01 PM...05...09...00...HST: SSR engineering playback

For readers interested in a bit more detail about today's ACS repair work, here is an explanation provided by Burch in an earlier interview with CBS News. He said engineers initially were "pretty negative" about attempting any sort of ACS repair.

"We knew how long it was taking us to get the STIS repair done," he said. "That took us over three years to get that done. And when ACS failed, we didn't have the luxury of three years to get that together. That kind of told us this was going to be a huge challenge. Second of all, we had failures on both sides of the main electronics box, 1 and 2, which we had on STIS also. But the problem was that on ... one of the sides (of the ACS), we couldn't get into the box because it was blocked by the NICMOS cooling system and we'd have had to disassemble that partially to get in there and nobody wanted to do that. The other side that was accessible was difficult to get at and if you got it open, we were concerned about a contamination risk because of the catastrophic nature of the failure. So much current went through there that we we thought there was the potential for a lot of collateral damage and you open that box up and it's like Pandora's box, you don't know what's coming out of there and we didn't think that was a healthy scenario.

"So we had to come up with a whole new approach to repairing ACS," he said. "We can't get into either of the low-voltage power supplies on ACS. So our approach is, we're going to provide an additional low-voltage power supply and we'll just hang it on the outside of the instrument and we'll tap into the power connector coming into the instrument. So we'll kind of T off the power to that. Ideally, we'd like to restore both the wide-field channel and the high-resolution channel on the ACS. It turns out, even though the high-resolution channel, as the name implie,s provides the best, the deepest pictures, the most sensitive and the highest resolved pictures, it was not the most popular channel by the astronomers because of its very narrow field of view. They found the wide-field channel very useful for the majority of observations that they wanted to make. So the wide-field channel was used a very high percentage of the time, it was on the order of 70 some odd percent whereas the high-res channel was maybe 20 percent or less and the solar blind channel was like 5 percent.

"So we said OK, let's look at how we might do this. And the technique that we came up with, it turns out you can get access to the CCD electronics box that powers each of those channels, you can gain access to those somewhat conveniently going in through the outside of the instrument.

"You don't have to take off a bunch of covers and go through a lot of stuff to get at them. but it's not real easy, either. There are two CCD electronics boxes, one for the wide-field channel and one for the high-res channel. In order to get access to them, you have to cut off an EMI grid. There's like this screen, this very coarse screen on the outside. So we came up with a special cutter tool that cuts that screen away and it cuts the individual wires. There's roughly a dozen wires or so that need to be cut. Once you've done that, you're now looking at a plate that needs to be removed and it's got 30 some odd screws in it. So you put a fastener-capture plate on that and remove the screws and once you pull that plate out, you're now looking at four printed circuit boards in each of those cavities that contain the electronics that power and control the CCD for each of those channels.

"So the idea is, pull those boards out and put in a new set of boards but wire them up in a way that they bypass or ignore the damaged areas coming from the existing main electronic box. This new module that would go in that replaces those four boards, it'll be powered by the external low voltage power supply that you've just attached to the outside of the instrument and it in turn will provide the power and control signals to the CCD using the existing wires that are in there, but it can be done in a way that avoids the damaged areas in the main electronics box.

"The downside here is we just didn't have the time and the money to replace the electronics in both the wide-field channel's CCD electronics box and the high-resolution channel's CCD box. So we came up with a scheme, it turns out there are shared copper paths between the electronics for both of those channels. So what we said was, hey, why don't we get to the high-res channel through the electronics path that are connected to the wide-field channel? We'll just back power the existing printed circuit boards that are in the high-resolution channel CCD. We tested that on the ground and sure enough, it turns out to be feasible to do that. The only question mark is the status of the low voltage power supply on the MED 1 and MED 2 sides. In other words, it's possible that if there's damage on the sides of the interpoint converters, the secondary sides that are powering the high-resolution channel, it's possible there are some short circuits there that will prevent this scheme from working. Particularly on the one side that suffered the major damage. That may not work very well.

"In any event, what we decided to do is, we're providing an additional built-in power supply that will try to rejuvenate, or bring back to life, the high-resolution channel by back powering the high-res channel through these shared copper paths that connect to the wide-field channel," Burch said. "I won't say it's a long shot. It IS somewhat of a long shot, but people need to understand that this doesn't have the same degree of rigor as, let's say, building a brand new science instrument or a new black box that we're hooking up to standard interfaces that already exist on the telescope. This is really a bit of an experiment."

Even if ACS is revived, engineers would face yet another hurdle: "tuning" the CCD control electronics to get optimum performance.

"They go to great pains on the ground to tune the electronics to get optimum performance out of these things to get the best sensitivity," Burch said. "Unfortunately, the detectors are up there and we're down here and we don't have that opportunity. So the question is, well, how do you make that happen? What we did was, we borrowed some technology from James Webb Space Telescope. We have employed the use of an ASIC chip, an application specific integrated circuit known as a sidecar, which is basically a video processing chip. And this chip is going to be key to enabling us to fine tune the control electronics, the new electronics we're putting in for the wide field channel so that we can get the lowest possible read noise out of the system when it's installed on orbit and operating.

"We're very fortunate that we have an excellent flight spare detector for ACS right here on the ground. Actually, we have several and we've experimented with those and saved our final testing for the best chip. And so we were able to put this into a dewar, get the temperature down to what it's experiencing on orbit and we've been able to fine tune the electronics with the software to demonstrate that this technique works and that we can get the kind of performance that we're looking to achieve. As a matter of fact, I probably shouldn't say this, if it works out up there the way it's worked out on the ground we'll be getting better pictures out of the ACS wide field channel than before the failure occurred."

Developing the ACS repair concept and perfecting the techniques required has required "a super human effort," Burch said.

"This is fine work using new tools, this is stuff that hasn't been done before, getting access to this ACS CCD electronics box area is very, very difficult because it's up near the top of the instrument, there's some structure that's in the way that makes getting direct viewing of this area exceedingly difficult. We've had to build and modify tooling to get in there. It's going to be tough. With the bulky suits and gloves, it's going to be tough work."

But "if these instrument repairs don't go well, they won't do any harm to the observatory so we won't be any worse off for not having tried."

For his part, Grunsfeld said he's confident the astronauts can successfully repair both broken instruments.

"The extra time we've had with the flight delay has allowed us to practice over and over again the removal of these tiny screws," he told CBS News. "For both the STIS repair, with Mike Massimino at the screw driver, and myself for the Advanced Camera for Surveys repair, we've really honed it to the maximum efficiency. As a result, I have high confidence going into it that we'll be able to finish it in the EVA day, maybe a slightly extended EVA day, but that's in the absence of any surprises. And one thing I've learned from the first two missions and involvement in all the Hubble missions is, Hubble is always full of surprises. So we'll have to see on the day we get there."

Burch said he believes "the odds are better than 50-50 for ACS and I think they're much better than 80 percent for STIS. But I hope I don't have to eat my words after this mission."


5:00 PM, 5/15/09, Update: Spacewalk No. 2 ends

Astronauts Michael Massimino and Michael "Bueno" Good began repressurizing the shuttle Atlantis' airlock at 4:45 p.m. to wrap up an extended seven-hour 56-minute spacewalk to install six gyroscopes and three batteries aboard the Hubble Space Telescope.

The Hubble Space Telescope, after installation of batteries
and gyroscopes (Photo: NASA TV)

Originally planned for six-and-a-half hours, the EVA began at 8:49 a.m. But problems getting one of three dual-gyro rate sensor units installed threw the astronauts well behind schedule. In the end, they had to forego one state-of-the-art gyro pack and instead install a refurbished RSU taken from Hubble during a 1999 service call.

They had no problems of any significance replacing one of two battery modules containing three nickel-hydrogen batteries. The other module will be installed during a spacewalk Monday.

With today's excursion, the Atlantis astronauts have logged 15 hours and 16 minutes of spacewalk time through two of five planned EVAS. Through five servicing missions, total Hubble EVA time now stands at 144 hours and 26 minutes by 16 different astronauts. This was the third Hubble EVA for Massimino and the first for Good.

"It was really great going out there today for the first time," Good said from the shuttle's airlock. "Big thanks to everybody on the ground, incredible effort."

"I'd like to echo what Mike said. And Mike, it was a pleasure going out with you, an honor, on your first EVA, you did a great job. There's about a million people to thank for getting us ready for RSUs and batteries."

Lead spacewalker John Grunsfeld, who helped orchestrate today's EVA from inside Atlantis, offered congratulations, saying "those gyros are crucial and Hubble's batteries are getting old. You did a fantastic job."


2:40 PM, 5/15/09, Update: Astronauts, behind schedule, agree to extend spacewalk to get Hubble battery pack installed

Running two hours behind schedule after problems installing three gyro packs, astronauts Michael Massimino and Michael "Bueno" Good agreed to extend their spacewalk to get a critical battery pack installed aboard the Hubble Space Telescope.

"We're down probably two hours, at 5:45 (elapsed time) right now," astronaut Dan Burbank radioed from Houston. "The limiting consumable, really, is currently Mass's O2 (oxygen), sitting at about 8:10 total. We can fix that very easily just by connecting to the SCU (airlock air supply), just about five minutes, he should be good. The next limiting consumable after that is Bueno's battery at about nine hours. So we think we've got plenty of time and I think you gave us some input already about your interest in the battery task."

"OK, thanks for that," John Grunsfeld replied from Atlantis. "Mass and Bueno, I assume you're up for batteries?"

"Sure," Massimino replied.

Flight controllers said the crew could sleep an extra hour in the morning and commander Scott Altman made one final check with the spacewalkers to make sure they had no concerns about an extended excursion.

"Bueno, how you doing?" Altman asked.

"What's the PET (elapsed time)?" Good asked.

"We're at about six (hours)," Grunsfeld replied.

"And what's normal batteries, and coming in?"

"We've got two hours more of work left," Grunsfeld said.

"We show that Bueno has three more hours on battery," Burbank said.

"Yeah, copy that, I don't have that much on internal battery, though," Good said. "I'm right on the edge now, I'm willing to give it a try."

"OK. Mass, how you doing?" Altman asked.

"I'm OK."

"All right, Bueno, we'll try to keep it moving."

Helmet cam view of Good working on battery replacement
(Photo: NASA TV)

A few minutes later, Altman gave the spacewalkers a bit of a pep talk, saying "Hubble again threw us some curves today."

"You guys did a great job responding to that," Altman said. "Bueno, you're twice as strong as the (robot) arm because you pushed me back down a couple of times, so I know that took a lot of effort there. Hopefully we can give you a break for these last couple of tasks without too much physical requirements. But no promises, we'll see what happens. Great job, keep it up, we'll see you inside in a little bit.

Added Grunsfeld: "That was really outstanding work. As usual, Hubble threw us quite a few problems and we've got our fingers crossed batteries will go a little bit more smoothly."


02:15 PM, 5/15/09, Update: Two new gyro packs, one refurbished unit installed on Hubble

Astronaut Michael Massimino, inside the Hubble Space Telescope, and fellow spacewalker Michael "Bueno" Good, on the end of the shuttle Atlantis' robot arm, successfully installed four state-of-the-art gyroscopes in the Hubble Space Telescope today. But an alignment problem prevented installation of a box containing a final two gyros and the astronauts were forced to install a refurbished spare in its place.

Installing the new gyros was the top priority in the five-spacewalk servicing mission and engineers at the Goddard Space Flight Center in Greenbelt, Md., verified that all six gyros were properly connected and working properly.

"Mass and Beueno, my friend (King) Leonidas has a couple of words for you guys that are appropriate right now," Atlantis commander Scott Altman joked. "'Remember this day, men, for it will be yours for all time.'"

"Thanks, Scooter. We've got a little more work to do, but thanks," Massimino replied. "Thank very much."

He was referring to installation of a new battery pack, the first of two that will be installed during Atlantis' mission. The gyro installation problem put the spacewalkers about an hour and a half behind schedule.

Good's helmet cam view of Massimino inside the Hubble
Space Telescope (Photo: NASA TV)

With Massimino anchored inside the telescope, moving cautiously because of close proximity to sensitive star trackers, the two spacewalkers started with RSU No. 2 in the upper right corner of an equipment bay. The process required Massimino to detach two electrical cables and for Good, operating a power drill with a long socket fitting, to unscrew the bolts holding the box in place.

Good then attached the replacement RSU to an extension tool and carefully passed it into the telescope to Massimino. Once positioned properly on guide pins, Good would drive bolts to secure the replacement unit.

Massimino's helmet cam view of good outside the Hubble
Space Telescope (Photo: NASA TV)

The process worked fine for RSU 2. But when the astronauts attempted to install a new gyro pack, serial number 1007, in the RSU 3 position in the upper left corner of the equipment bay, they ran into problems. Despite repeated attempts, they were unable to get the new unit aligned on the guide pins well enough to permit the bolts to engage.

Good said it felt like the new unit was rocking slightly on its mounting plate, indicating a problem that prevented it from sitting flush and preventing the bolts from engaging. After discussing the issue with the ground, it was decided to temporarily store the 1007 RSU and to mount the box intended for the RSU 1 position.

"I'm not too confident this is going to fit anywhere," Good said at one point, referring to 1007.

But the astronauts pressed ahead and had no problems installing the RSU 1 unit in the RSU 3 slot.

"All right, Mike, let's get it," Massimino said.

Once in position, the astronauts put the RSU in position and Good drove in the bolts to secure it.

"Three (turns), four, five, I definitely got it," Good reported.

"Excellent," Massimino replied. Cheering could be heard from the shuttle's flight deck.

"You're my hero," Massimino said. "Yeah, that bolt is in. Great job, Mike."

After a second bolt was driven home, someone wryly observed: "Double-oh seven double crossed us!"

"Ah hah!" Massimino said.

The astronauts then moved to RSU position 1 and removed the old unit. But again, they were unable to get the 1007 box to fit flush on the mounting plate. Flight controllers gave Good permission to make additional attempts, but John Grunsfeld, an astronomer-astronaut making his third visit to Hubble, said he disagreed.

"It's really your guys' call, of course, but I'm a little uncomfortable with trying to make an inertial platform out of something that may not be installed flat, even if we get one of the bolts done," he said.

"John, we copy and we agree with that plan," astronaut Dan Burbank replied from Houston.

Massimino and Good then returned to an equipment carrier and retrieved a spare RSU that was carried aloft as a backup. The spare unit was removed from Hubble during a servicing flight in 1999 and then refurbished. It does not feature some of the improvements built into the RSUs installed in positions 2 and 3 and as such, it may not operate as long as the new models. But Hubble can be operated with just two gyros and, in extreme cases, just one.

As it turned out, Good had additional problems getting the spare unit in place but he eventually succeeded.

"Atlantis is pleased to report RSU 1 connectors are mated," Good said.


9:30 AM, 5/15/09, Update: Spacewalk No. 2 begins

Astronauts Michael Massimino and Michael Good, floating in the shuttle Atlantis' cramped airlock, switched their spacesuits to internal battery power at 8:49 a.m. to kick off a planned six-and-a-half-hour spacewalk to replace the Hubble Space Telescope's batteries and stabilizing gyroscopes. Both astronauts floated into the shuttle's cargo bay a few moments later and began setting up tools and equipment needed for the gyro installation.

Flight controllers, meanwhile, are troubleshooting a possible icing problem with the shuttle Atlantis' flash evaporator, a critical cooling system that supplements the shuttle's radiators in orbit and provide primary cooling during launch and re-entry. It's also used to help get rid of excess water during orbital operations.

"We think it might be an ice issue," Dan Burbank radioed from mission control in Houston. "Weren't really sure that was the signature, but we're in a good config right now as far as supply water and FES for the rest of the day."

Additional troubleshooting may be carried out later today if the problem persists, but there was no immediate impact on today's operation.

Massimino and Good, meanwhile, are pressing ahead with the gyro replacement work, getting in position to open access doors on the space telescope.


06:50 AM, 5/15/09, Update: Massimino, Good prepare for EVA-2

Astronauts Michael Massimino and Michael "Bueno" Good are preparing for a six-and-a-half-hour spacewalk to swap out the Hubble Space Telescope's six stabilizing gyroscopes - the top priority of Servicing Mission 4 - and three of its aging nickel-hydrogen batteries, now operating at half their original capacity.

"They are 20 years old," said Hubble Program Manager Preston Burch. "They were built a couple of years before we launched in '90. We're so far beyond the design lifetime it's anybody's guess as to how long they could continue to go. We know it's not infinite. So our best judgment is we should go ahead and still change them out."

Hubble's gyroscopes, which help it lock onto and track its targets, are an even more pressing concern. The telescope was designed with redundancy in mind and while it was equipped with six gyros, only three were required for science operations. But gyros 2, 3 and 5 have failed and gyro 6 exhibits symptoms of a problem that eventually could knock it out of action.

"We're flying on one and six," Burch said. "Four is in reserve, However, six, you may recall, has some flaky characteristics that were detected not too long after it was installed on servicing mission 3A (in 1999). We suspect it has to do with the suspension system in it. When you slew the observatory, the drift rate on the gyro changes significantly on it. That's the bad news. The good news is, it changes in a very predictable way. We cleverly put some flight software on board that enables us to use gyro 6 and not be confused or whatever by the shift in the gyro drift bias.

"Now gyro one recently had a sudden surge in its motor current which is indicative of a temporary rotor restriction event. And this has happened (several) times. The current has gone up, but it's come back down. But it's still running at a value slightly higher than normal. So our best experts and our past experience tell us one is living on borrowed time and it could go at any time. Gyro four, although it's off and held in reserve, was used for a long time and has a lot of run time on it. It's up there, it's up around the 50 percent point in terms of probability of failure. It's not clear how long gyro four could last if and when we had to turn it on and use it.

"So the bottom line is, all three of the remaining gyros have got liens against them if you will," Burch said. "Six because of the flaky suspension, one because of the flaky motor current and four because it's got a lot of run time on it. So you ask, how much longer can you guys keep going on gyros, even with a one-gyro science mode, and that becomes highly speculative. ... Our previous calculations showed we could probably get through 2009 with the gyros that we have. I think getting much past 2010 would be a bit of a stretch."

Today's spacewalk was scheduled to begin at 8:16 a.m. Massimino and Good plan to change out all six gyros and to replace three of the telescope's six batteries. The other three, in a different location, will be swapped out during a spacewalk Monday.

During preparations early today, flight controllers informed the astronauts that the new $132 million Wide Field Camera 3, installed during the crew's first spacewalk Thursday, had passed an overnight "functional test.

"Hey, while I've got you guys, the Goddard (Space Flight Center) team reports we got a good functional test on Wide Field 3," astronaut Dan Burbank called from Houston.

"That's great news, Dan," Massimino replied.

For identification, Massimino, call sign EV-3, will be wearing a spacesuit with horizontal broken stripes while Good, EV-4, will use a suit with barber pole stripes. Massimino will be the designated "free floater" while Good will spend much of the day anchored to the end of the shuttle's 50-foot-long robot arm.

This will be the 20th spacewalk devoted to Hubble servicing, the second of five planned for Atlantis' mission, the third for Massimino, veteran of the most recent previous Hubble servicing mission in 2002, and the first for Good. Going into todays's EVA, 15 astronauts have logged 136 hours and 30 minutes working on the space telescope, including seven hours and 20 minutes logged Thursday by Atlantis astronauts John Grunsfeld and Andrew Feustel.

Replacing the gyro packages is not overly complex - each two-gyro rate sensor unit is held in place by three bolts and two electrical connectors - but it requires an astronaut to float well inside the telescope, within inches of delicate equipment that could be damaged by an inadvertent movement.

"The access to the RSUs is really the hard part," said Tomas Gonzales-Torres, the lead spacewalk officer at the Johnson Space Center. "The task itself is a couple of connectors and some bolts and you take a box out. But it's really the access inside of the telescope that makes it difficult."

Massimino described the work as "one of the more challenging (tasks) that we do."

"Mike Good is on the robot arm," he said. "I'm going to get inside the telescope and then more or less I'll stop at one point and he has to rotate me on my back. And then put my feet in the foot restraint - we have a PFR (portable foot restraint) set up inside the telescope - because if I was to try to get in myself there's a good chance I would knock something I'm not supposed to. So pretty much go inside and act like a statute ... and let the other guy control you, move your body around and get your feet in the foot restraint.

"And then, once I'm inside there, I get pretty close to the star trackers, which are the things you don't want to hit. ... My chest will come up within an inch or so of the star trackers. If you damage it, it's kind of like game over. It's the likely end of the telescope. if you just nudge it a little bit, it's not the end of the world but you'd have to recalibrate everything. Because those are the things, part of the system that works with the RSUs that help point the telescope really accurately."

After the rate sensor units are replaced, Massimino and Good will turn their attention to replacing three batteries, in one box, in equipment bay 2. The battery module is mounted on the equipment bay door, held in place by 14 bolts and six electrical connectors.

"Each battery has 22 cells in series along with heaters, heater controllers, pressure measurement transducers and electronics, and temperature-measuring devices and their associated electronics," according to the NASA/Lockheed Martin Servicing Mission 4 media guide. "Three batteries are packaged into a module measuring roughly 36 x 36 x 10 inches and weighing about 475 pounds. Each module is equipped with two large yellow handles that astronauts use to maneuverthe module in and out of the telescope."

Good, on the end of the shuttle's robot arm, will remove the old bay 2 battery module and hand it off to Massimino, who will hand him a new unit. While Massimino stores the old battery pack for return to Earth, Good will move back up to equipment bay 2 and install the replacement.

Here is an updated timeline of today's activity (in EDT and mission elapsed time; includes revision C of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05/15/09

04:31 AM...03...14...30...Crew wakeup
05:46 AM...03...15...45...EVA-2: Preparations begin
07:01 AM...03...17...00...Tile inspection
07:16 AM...03...17...15...EVA-2: Spacesuit purge
07:26 AM...03...17...25...EVA-2: Spacesuit pre-breathe
08:06 AM...03...18...05...EVA-2: Airlock depressurization
08:16 AM...03...18...15...EVA-2: Spacesuits to battery power
08:21 AM...03...18...20...EVA-2: Airlock egress and setup
09:01 AM...03...19...00...EVA-2: Rate sensing unit replacement
12:21 PM...03...22...20...EVA-2: Bay 2  battery pack
01:56 PM...03...23...55...EVA-2: Cleanup and airlock ingress
02:01 PM...04...00...00...HST: Battery aliveness test
02:36 PM...04...00...35...HST: Solar arrays slewed to 90 degrees
02:41 PM...04...00...40...EVA-2: Airlock repressurization
02:51 PM...04...00...50...Spacesuit servicing
03:01 PM...04...01...00...HST: Battery functional test
03:30 PM...04...01...29...Mission status briefing on NTV
03:56 PM...04...01...55...EVA-3: Tools configured
03:56 PM...04...01...55...LIOH and battery config
04:16 PM...04...02...15...Spacesuit swap
04:21 PM...04...02...20...HST: Solar arrays slewed to 0 degrees
04:41 PM...04...02...40...HST: RSU functional test
05:06 PM...04...03...05...HD crew choice downlink
05:11 PM...04...03...10...EVA-3: Procedures review
08:31 PM...04...06...30...Crew sleep begins
08:45 PM...04...06...44...HST update on NTV
09:00 PM...04...06...59...Daily highlights reel
09:01 PM...04...07...00...HST: SSR engineering playback
11:00 PM...04...08...59...ISS-20 pre-launch activities

Here is a description of today's spacewalk from NASA's STS-125 press kit:

For their first spacewalk of the STS-125 mission, Massimino and Good will spend the bulk of their time replacing three rate sensor units. Each unit is part of a rate gyro assembly, which sense vehicle motion and provide rate data for the telescope. The replacement units will be stored inside a protective enclosure inside the shuttle's cargo bay. Massimino will open the lid of the enclosure to allow Good, who will be riding the space shuttle's robotic arm for the spacewalk, to retrieve the first unit and carry it to the telescope. Massimino will also retrieve a gripper tool that Good will use to maneuver the units into place.

At the telescope, Good will retract two fixed head star tracker seals, allowing the doors on the telescope bay that the crew will be working in to open. Once open, Good will move a cross aft shroud harness inside the telescope to make room for the foot restraint Massimino will be using. Massimino will retrieve the foot restraint for Good to install, then Good will help Massimino into it. To remove the old rate sensor units, Massimino will disconnect two electrical connectors, while Good removes three bolts. The same connectors and bolts will need to be connected and tightened to install the replacement unit.

The two spacewalkers will repeat this process two more times as they replace the remaining two rate sensor units. If time permits, Massimino and Good will do some get-ahead work for the third spacewalk of the mission by installing a power input element harness for the Advanced Camera for Surveys before they move the cross aft shroud harness back into place and close the doors on the worksite.

After the new rate sensor units are installed, Massimino and Good are scheduled to perform the first half of the mission's battery replacement work. They'll be working in the telescope's Bay 2 to replace the first of two batteries. Good will retrieve the old battery by disconnecting six electrical connectors and unscrewing 14 bolts, while Massimino retrieves the new battery from its stowage location inside the shuttle's super lightweight interchangeable carrier. He'll have to unscrew 12 bolts to remove it. The two astronauts will swap batteries at the carrier, and Good will transport the new battery to the telescope for installation, while Massimino stows the old.


04:50 PM, 5/14/09, Update: Spacewalk No. 1 ends (UPDATED at 7:45 with comments from mission managers)

John Grunsfeld and Andrew Feustel successfully installed a powerful new $132 million camera and a critical science data computer on the Hubble Space Telescope Thursday during a roller coaster of a spacewalk that brought to mind the "Perils of Pauline" history of the fabled observatory.

"Well, we got to Hubble and gave Hubble a hug," Grunsfeld said from the airlock when the work was done. "But in traditional Hubble fashion, Hubble threw us a few curves. But I think it's really a testament to the whole team on board here and of course, on the ground ... that we were able to overcome them and that we have a Wide Field Camera 3 in the telescope, which will help unlock the secrets of the universe, and a new scientific instrument command and data handling (computer)."

The spacewalk began at 8:52 a.m. and ended with airlock re-pressurization at 4:12 p.m. for a duration of seven hours and 20 minutes. It was the 19th EVA devoted to servicing the Hubble Space Telescope, the first of five planned by the Atlantis astronauts, the sixth for Grunsfeld and the first for Feustel. Total Hubble EVA servicing time now stands at 136 hours and 30 minutes. Grunsfeld's total EVA time through six spacewalks stands at 44 hours and 52 minutes, putting him eighth on the list of most experienced spacewalkers.

The first item on the agenda today was installation of the new Wide Field Camera 3 in place of the aging Wide Field and Planetary Camera 2, which was installed during the first Hubble servicing mission in 1993. Attempting to remove the old camera, Feustel initially was unable to loosen a critical bolt holding the instrument in place.

Grunsfeld then returned to the shuttle's airlock and retrieved a torque limiter, allowing Feustel to safely apply more force. The bolt would not budge. Flight controllers then approved a last-ditch contingency plan, telling Feustel to remove the torque limiter and apply more elbow grease to the socket.

"That A latch was at a higher torque than we could release initially," said lead spacewalk officer Tomas Gonzales-Torres. "So we used a multi-torque limiter that has different settings we can use. ... The one they nominally use is maxed out at 38 foot pounds. We have a contingency one that can be set at 45 foot pounds. So that's what the crew did, they went and retrieved the contingency MTL and unfortunately, that still was not high enough."

It was a make-or-break moment of high drama. But when Feustel applied the socket directly to the bolt and leaned into it, the bolt finally released.

"The failure torque of the bolt was 57.1 foot pounds," said Gonzales-Torres. "Without a torque limiter in place to limit the torque, the crew could impart, there was a possibility that you shear the bolt. If that happened, the instrument was going to be staying inside. WFPC 2 would stay inside the telescope and we would re-engage the connectors and the ground strap. It would still be a functional instrument, we just would not be able to get it out."

Project scientist David Leckrone said engineers were thrilled when the bolt finally broke free.

"I don't normally reveal my age and I'm not going to here, but I can tell you I'm five years older now than I was when I came to work this morning," he told reporters later. "Many of us have worked on WFC 3 on the order of 10 years or more, a lot of blood, sweat and tears. And we were concerned we might not end up with our highest priority instrument in."

Taking off the torque limiter was "near the bottom of the list" of contingency procedures, Leckrone said. When the bolt was freed, "there was just a huge outburst of elation and emotion."

From that point on, the camera swap out went smoothly and the Wide Field Camera 3 was successfully installed.

"We can sleep pretty well tonight, knowing that's been accomplished," Leckrone said.

Installation of the replacement science instrument command and data handling system computer also went smoothly. Grunsfeld then attached a grapple fixture to the base of the telescope to enable a future crew, or a robotic spacecraft, to drive Hubble safely into the atmosphere at the end of its life.

The final items on the agenda were installation of door latches intended to make it easier to access critical hardware during the crew's upcoming spacewalks. Two of four "latch over center kits," or LOCKS, were installed, but the astronauts had problems getting two others attached. Instead, one different type of latch and a door restraint were attached to accomplish the same purpose.

"It's been a tremendous day for the HST program," said Hubble Program Manager Preston Burch. "This is a huge accomplishment, our first EVA day in more than seven years, and the crew were able today to accomplish two out of our three highest priority items."

As they collected tools and tethers before heading back to Atlantis' airlock, the astronauts took a moment to marvel at the view of hometown Houston 350 miles below.

"Now that's a good view," Feustel marveled. "Oh, oh, wow!"

"How come that always happens when I'm under the telescope?" Grunsfeld wondered.

"I don't know, but I'm staring right at it," Feustel said. "Awesome!"

"Get the camera, Drew."

"Too late."


2:30 PM, 5/14/09, Update: Replacement science computer installed

Astronauts John Grunsfeld and Andrew Feustel successfully replaced critical computer gear on the Hubble Space Telescope today that should restore full redundancy to a critical system that formats and relays science data to the ground.

The shuttle Atlantis' launch was delayed seven months because of a failure last September that knocked out one of the two channels in Hubble's science instrument command and data handling system computer. A ground test unit was inspected, tested and certified for launch aboard Atlantis to restore full redundancy to the system.

The SIC&DH is mounted on the inner surface of an access door on equipment bay 10. The astronauts had no problems removing the old SIC&DH and the replacement unit was attached without incident. After an electrical harness was reconnected, engineers at the Goddard Space Flight Center in Greenbelt, Md., sent commands to verify connectivity and basic functions.

"Hey, happy to report we have a good aliveness test on SIC&DH-R," reported Dan Burbank from mission control in Houston.

"Fantastic," replied Grunsfeld.

"Wow, fantastic, great news, Dan. Thanks, a crew member added.

Andrew Feustel's reflection, viewed with his helmet cam, in the Hubble
Space Telescope (Photo: NASA TV)

With the replacement SIC&DH installed, Grunsfeld moved to the bottom of the space telescope and quickly attached a 72-inch-wide grapple fixture that will permit future astronauts, or a robotic spacecraft, to lock on and safely drive the observatory into the atmosphere for a harmless re-entry at the end of its lifetime

The final task on today's agenda was installation of door fixtures, and lubrication, that will make it easier to open access doors later in the mission.


12:50 PM, 5/14/09, Update: New camera installed; passes 'aliveness' test; replacement data computer installation on tap

After struggling to remove an old camera from the Hubble Space Telescope, spacewalkers Andrew Feustel and John Grunsfeld installed a powerful new camera in its place that should help Hubble peer deeper into space and time than ever before.

John Grunsfeld, left, and Andrew Feustel, on robot arm, complete
installation of Wide Field Camera 3 (Photo: NASA TV)

The $132 million Wide Field Camera 3 was mounted in place just before noon and ground controllers began a series of electrical checks, confirming the new instrument was plugged in and operating as expected.

"And Houston, for EVA," called Dan Burbank from mission control. "Good news ... aliveness test on Wide Field 3 is good."

"That's awesome news, Dan, thanks," replied Mike Massimino from Atlantis. "These guys did a great job and we appreciate all the great support we got from the ground getting Wide Field in to unlock the secrets of the universe."

"MORE of the secrets," chimed in astronomer-astronaut John Grunsfeld.

"MORE of the secrets of the universe," agreed Massimino.

Feustel and Grunsfeld ran into problems installing the old Wide Field Planetary Camera 2 in the same storage box used to launch its replacement. In this case, a recessed bolt did not initially engage. But after several attempts, Feustel finally was successful and the camera was safely stowed for the trip home.

The Wide Field Planetary Camera 2 extending from its storage box
(Photo: NASA TV)

The camera swap-out was complete by around 12:35 p.m., about an hour behind schedule because of the initial problems removing WFPC 2. The astronauts then turned their attention to the spacewalk's second major objective, installing a replacement science instrument command and data handling system computer, or SIC&DH.

Atlantis' launch was delayed seven months because of a failure last September that knocked out one of the two channels in Hubble's SIC&DH, which plays the critical role of formatting science data for transmission to Earth. A ground test unit was inspected, tested and certified for launch to restore full redundancy in the system.

The SIC&DH will be mounted on the inside of the access door to equipment bay 10, a quarter of the way around the telescope to the left of the Wide Field Camera 3.


11:10 AM, 5/14/09, Update: After high drama, astronauts remove old camera from Hubble

In a make-or-break attempt to free a stuck bolt holding an old camera in place on the Hubble Space Telescope, astronaut Andrew Feustel, anchored to the end of the shuttle Atlantis' robot arm, used old-fashioned elbow grease to save the day, releasing the bolt and clearing the way for installation of a powerful new camera.

If the bolt had snapped - and that was a possibility - the astronauts would have been unable to remove the 16-year-old Wide Field Planetary Camera 2. In that case, the new $132 Wide Field Camera 3 would have been returned to Earth aboard Atlantis in a major disappointment for the Hubble team.

But after removing a torque limiter from his wrench and applying more muscle power, Feustel was able to loosen the bolt to the relief of concerned flight controllers. He and partner John Grunsfeld then removed the old camera without incident.

Dubbed "the camera that saved Hubble" by project scientists, WFPC 2 took most of the spectacular photos that have made Hubble a national icon since it was installed in the telescope during the first servicing mission in 1993.

"It's been in there for 16 years, Drew, and it didn't want to come out," Grunsfeld said.

Andrew Feustel, on the shuttle's robot arm, and John Grunsfeld
pull Wide Field Planetary Camera 2 from the Hubble Space Telescope
(Photo: NASA TV)

Feustel first attempted to back off the bolt using the torque limiter and was unsuccessful. Grunsfeld returned to the shuttle airlock, retrieved additional tools and sockets and Feustel tried again. And again, he was unsuccessful.

"Drew, do you have any other suggestions before I check with Houston?" astronaut Mike Massimino called from inside the shuttle.

"No, I'm afraid I don't. I'm out," Feustel said.

Working through a contingency checklist, Feustel then removed the torque limiter from his wrench - the device that was limiting the applied torque to 45 inch pounds - before trying to apply more elbow grease directly to the stuck bolt.

"I just want to understand how far can we go with this and what are the implications if I over-torque and break the bolt?" Feustel asked. "Are you sure you want to know?" Massimino quipped. "Houston, Atlantis, you might have copied Drew's question. We know the failure torque on this bolt is 57.1 foot pounds," Massimino radioed. "He had the MTL (multi-setting torque limiter) set at 45. What the crib sheet says if we don't get it to break (loose) here, we're going to reconnect the ground strap and blind mate connector. So I guess Drew's just wondering how hard he should try on this A latch? If you have any words for us, we'd appreciate it."

"Atlantis, Houston, we copy that. And thanks for asking," replied Dan Burbank in mission control. "There's actually no issue with having the latch taken all the way to the failure point. The instrument should still function. So Drew can have at it, and you're correct, if we get to that point, we will need to reconnect the ground strap blind mate connector and we'll just leave it as is."

"So in other words, he can use what he needs from his strength to try to break the torque, is that what you're telling us?" Massimino asked.

"That's exactly right," Burbank said. "And as soon as he does, if he's successful, starts to have some motion in the latch, we'd like to go ahead and stop at that point."

"OK, thanks, Dan."

"OK, but I think we understand if it breaks, then Wide Field (Planetary Camera 2) stays in," Grunsfeld chimed in, verifying the make-or-break nature of the next step.

"What john said is correct," Burbank confirmed.

"OK, here we go," Feustel said, attaching the socket, sans torque limiter, to the attach bolt. Then, a moment later: "I think I got it! It turned, it definitely turned. And it's turning easily now."

"OK, Atlantis, Houston, for EVA, we copy, that's great news," Burbank said.

A few minutes later, Feustel attached a power wrench and backed the bolt out all the way to free the camera.

"Woo hoo, it's moving out" he said.

"That's great news," Massimino said. "That's awesome."

With astronaut Megan McArthur operating the robot arm from inside the shuttle's crew cabin, Feustel carefully pulled WFPC 2 out of the space telescope at just before 11 a.m. to accomplish the first primary objective of today's spacewalk. After securing the camera on the side of the payload bay, he and Grunsfeld will retrieve the new Wide Field Camera 3 from its storage container in the shuttle's cargo bay so it can be installed in the telescope in place of WFPC 2.

Earlier today, Feustel provided a brief report on contamination that was spotted on the WFC 3 carrier box after launch.

"For you in Houston, just looking at the front of the W-SIPE (Wide Field Camera scientific instrument protective enclosure), I don't really see any of those particles, there's maybe a really small amount of what kind of looks like dust, but it's pretty minor," Feustel reported. "It's almost imperceivable. I can see some few particles on the front of the W-SIPE, little, whitish, grey looking, real small. It's low density, too."


9:05 AM, 5/14/09, Update: Spacewalk No. 1 begins

Floating in the shuttle Atlantis' airlock, astronauts John Grunsfeld and Andrew Feustel switched their spacesuits to internal battery power at 8:52 a.m., 36 minutes behind schedule, to officially kick off a planned six-and-a-half-hour spacewalk. The primary goals of today's excursion are to equip the Hubble Space Telescope with a powerful new camera and to install a replacement data computer.

"Oh, this is fantastic!" Grunsfeld exclaimed as he floated into the shuttle's cargo bay. "You're going to love it, Drew."

John Grunsfeld exits the shuttle Atlantis' airlock
(Photo: NASA TV)

Based on the actual start time for today's spacewalk, here is an updated timeline of key events (in EDT and mission elapsed time):
EDT........DD...HH...MM...EVENT

05/14/09
08:52 AM...02...18...51...EVA-1: Spacesuits to battery power
09:57 AM...02...19...56...EVA-1: WFC 3 installation
09:57 AM...02...19...56...HST: WFC3 aliveness test
12:12 PM...02...22...11...EVA-1: SI C&DH (data computer) installation
01:32 PM...02...23...31...HST: SI C&DH aliveness test
01:37 PM...02...23...36...HST: SI C&DH functional test
01:42 PM...02...23...41...EVA-1: Grapple fixture and door handles
02:37 PM...03...00...36...EVA-1: Cleanup and airlock ingress
03:22 PM...03...01...21...EVA-1: Airlock repressurization


6:45 AM, 5/14/09, Update: Astronauts set for first Hubble spacewalk

Astronauts John Grunsfeld and Andrew Feustel are gearing up for a planned six-and-a-half-hour spacewalk today to equip the Hubble Space Telescope with a powerful new camera and a replacement data processing computer. The spacewalkers also plan to install new handles on Hubble equipment bay doors to improve access and a grapple fixture that will permit future astronauts, or a robotic spacecraft, to latch onto the telescope so it can be driven out of orbit at the end of its life.

Floating in the shuttle Atlantis' airlock, Grunsfeld, making his sixth spacewalk, and Feustel, making his first, plan to switch their spacesuits to internal battery power at 8:16 a.m. to officially kick off today's excursion. Commander Scott Altman said Wednesday, however, the crew may begin the spacewalk early if preparations go smoothly.

This will be the 19th spacewalk devoted to Hubble servicing and the first of five planned for Atlantis' mission. Going into todays's EVA, 14 astronauts have logged 129 hours and 10 minutes working on the space telescope during four previous servicing missions in 1993, 1997, 1999 and 2002.

For identification purposes, Grunsfeld, call sign EV-1, will be wearing a suit with red stripes on the legs while Feustel, EV-2, will be wearing a suit with no stripes. Grunsfeld will be the designated 'free floater" while Feustel will be anchored to a foot restraint on the shuttle's 50-foot-long robot arm for much of today's spacewalk.

"The moment I'm most looking forward to is the instant that I come out of the airlock, because we'll be, payload bay facing the Earth, and I'm anticipating the moment of peeking out with my head facing towards the Earth and just seeing the ... Earth 300 miles below me," Feustel said in a NASA interview. "I'm very excited about that, I'm hoping I don't lose myself in the moment and am able to continue, but it's going to be really exciting."

After exiting the airlock, hooking onto safety tethers, breaking out tools and installing the foot restraint on the robot arm, the astronauts will focus on replacing Hubble's current Wide Field Planetary Camera 2, installed during the first Hubble servicing mission in 1993, with the new Wife Field Camera 3.

While Feustel familiarizes himself with moving about in weightlessness, Grunsfeld will deploy a platform toward the rear of the payload bay, on the left wall, where the astronauts can temporarily stow the old camera while the new Wide Field Camera 3 is installed.

After Feustel retrieves a handling fixture, Megan McArthur, operating the shuttle's robot arm, will move him up to the camera work site in the side of the telescope. Feustel will install the hand rail on the WFPC-2, open latches and carefully slide the camera out. He and Grunsfeld will then mount it on the temporary platform Grunsfeld deployed earlier.

Both spacewalkers then will move to the WFC 3 storage container, open it and install a handling fixture, careful not to disturb any of the fine dust-like particulate that was discovered on the box earlier. Engineers are not sure what the white material might be, but they suspect it shook free from forward payload bay bulkhead insulation blankets during launch.

Feustel will pull the 900-pound WFC 3 from its container and McArthur will moved them both back to the side of the telescope. Both astronauts then will slide the camera into position using guide rails and lock it in place.

"Wide field is a pretty straight-forward task," said lead spacewalk officer Tomas Gonzales-Torres. "You drive one bolt to release it, remove a ground strap and pull the entire instrument out and that's it. It's a big box. The problem again is in the details, making sure you control it just right (during installation). Any little jitter that is left over after we leave is going to impact science."

After installing WFC 3, Grunsfeld and Feustel will move the old camera from its temporary mounting point and put it into the container used to carry WFC 3 into space.

The crew's second major task is replacement of Hubble's science instrument command and data handling system computer, which formats and routes science data to the ground. Last September, just three weeks before Atlantis' original launch date, one of the two data channels in the SIC&DH failed, leaving Hubble with no redundancy in a critical system. Mission managers decided to delay the shuttle launch to give engineers time to prepare a replacement in order to restore full redundancy.

The 136-pound SIC&DH is made up of six major components mounted on a single plate that will be attached to the inside of the door to equipment bay 10 by 10 bolts and a single cable connector.

"It's a relatively straight forward task, involving removal of bolts on a door, removing a connector, which he'll do by cranking a bolt, taking it off," Grunsfeld said. "We'll go down and swap it, he'll bring the new one back up and put it on. There are a number of subtleties, as there are on every task on Hubble where if you do something wrong you can screw it up. But it's a pretty high priority task to get that done given the failure in October. But it's pretty straight forward."

Assuming time is available, the spacewalkers will install equipment bay door handles to improve access and attach a grapple fixture on the base of the telescope.

"The idea is to make revisiting Hubble less risky and, hopefully, less costly," said Program Manager Preston Burch. "(Former Administrator) Mike Griffin said he did not want to preclude an option for a subsequent administrator to want to go back to Hubble. The idea would be most likely a robotic mission to attach a deorbit propulsion system. But we're using the low-impact docking system technology from the international space station so it would be compatible, potentially, with an Orion capsule."

Here is an updated timeline of today's activity (in EDT and mission elapsed time; includes revision B of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05/14/09
03:01 AM...02...13...00...HST: SSR engineering playback
04:31 AM...02...14...30...Crew wakeup
05:46 AM...02...15...45...EVA-1: Preparations begin
07:16 AM...02...17...15...EVA-1: Spacesuit purge
07:26 AM...02...17...25...EVA-1: Spacesuit pre-breathe
08:06 AM...02...18...05...EVA-1: Airlock depressurization
08:16 AM...02...18...15...EVA-1: Spacesuits to battery power
08:21 AM...02...18...20...EVA-1: Airlock egress and setup
09:21 AM...02...19...20...EVA-1: WFC 3 installation
09:21 AM...02...19...20...HST: WFC3 aliveness test
11:36 AM...02...21...35...EVA-1: SI C&DH installation
12:56 PM...02...22...55...HST: SI C&DH aliveness test
01:01 PM...02...23...00...HST: SI C&DH functional test
01:06 PM...02...23...05...EVA-1: SCM and locks
02:01 PM...03...00...00...EVA-1: Cleanup and airlock ingress
02:46 PM...03...00...45...EVA-1: Airlock repressurization
02:56 PM...03...00...55...Spacesuit servicing
03:30 PM...03...01...29...Mission status briefing on NTV
03:36 PM...03...01...35...HST: WFC3 functional test
04:01 PM...03...02...00...EVA-2: Tools configured
04:01 PM...03...02...00...Spacesuit swap
04:51 PM...03...02...50...HD TV downlink opportunity
05:01 PM...03...03...00...EVA-2: Procedures review
08:31 PM...03...06...30...Crew sleep begins
08:45 PM...03...06...44...Space telescope update on NTV
09:00 PM...03...06...59...Daily highlights reel on NTV
10:01 PM...03...08...00...HST: SSR engineering playback

For many members of the Hubble team, removal of the Wide Field Planetary Camera 2 will be a bittersweet moment. Dubbed "the camera that saved Hubble," WFPC 2 was equipped with corrective optics to counteract the spherical aberration that prevented the telescope's primary mirror from bringing starlight to a sharp focus. The camera was a huge success, taking most of the spectacular pictures familiar to the public.

"The Wide Field 2 camera, that was put in on the first servicing mission, was put in for a couple of reasons, but the primary one was that built into Wide Field Camera 2 was a little mirror that corrected the aberrated optics of Hubble, which was the big catastrophe when Hubble was launched," Grunsfeld said in a NASA interview.

"The technology that went into that camera was state of the art at the time, but we're talking about 1990. Imagine what kind of digital camera you could buy in 1990 - they weren't on the market yet. Well, nowadays, of course, you can go out and buy phenomenal cameras, and the astronomy community can create even better cameras for astronomical research with very large sensors, with lots and lots of pixels that can see over a wider range of frequencies.

"So Wide Field Camera 3 also will contain that little mirror that corrects the optics, but it will also have an infrared camera that can see light that's much longer (wavelength) than our eyes can see but is very important for astronomy, and visible and ultraviolet in another channel. So it has this infrared and this ultraviolet/visible channel, all of which have better detectors, more sensitive, that can see much, much dimmer things than the previous cameras could see, on any part of the telescope.

"Plus, it's a wide-field telescope, as it name sounds, so it can see larger extended objects," Grunsfeld said. "What kind of things are we talking about? Well, we're looking at everything from planets in our solar system, the moon even, out to perhaps the most distant galaxy that will ever have been seen, because of this increased sensitivity and because of the infrared part of the Wide Field Camera 3. As you look further and further back in time, because of the expansion of the universe, objects get redder and redder, they get red-shifted. And so this new Wide Field 3 camera promises, with the sensitivity of Hubble's optical system and the detector, to see further back in time, closer to the big-bang, than we've ever been able to see before."


6:55 PM, 5/13/09, Update: Shuttle tiles, blankets in good shape for entry; wing leading edge analysis continues, but no problems seen to date; presumed leading edge debris impact not considered serious (UPDATED at 8:10 p.m. with heat shield clearance)

NASA's Mission Management Team late Wednesday completed an initial assessment of the shuttle Atlantis' heat-shield tiles, blankets, reinforced carbon carbon nose cap and wing leading edge panels and decided no additional "focused" inspections will be needed until the end of the mission.

One small area of 16 tiles on the left side of the fuselage near the nose was not fully inspected because of a camera tracking overlap problem, but flight controllers told the crew those tiles could be inspected later, after an upcoming spacewalk, using the camera on the end of the shuttle's robot arm.

"The team's have been working very hard looking at all the data from all the survey work you guys did on flight days one and two and ... I can happily tell you no focused inspection is required," astronaut Alan Poindexter radioed from mission control in Houston.

"Well, that is good news," shuttle commander Scott Altman replied from Atlantis. "I know they had to work basically overtime, full-time, quarter-time, all the time to get all that work done and that data analyzed faster than we've done it before. So we appreciate that, it's great to know that tomorrow we can just focus on the EVA (spacewalk) and not worry about setting up for a focused inspection. So thanks to the team for all the work. We feel very good and confident in this report."

The Atlantis astronauts grappled the Hubble Space Telescope earlier Wednesday, mounting it in the ship's cargo bay for a five-spacewalk repair job. At Hubble's high altitude, the shuttle crew is at slightly higher risk - the mean value is 1-in-229 - from impacts with space debris.

Late Wednesday, flight controllers notified the astronauts they were tracking a 4-inch-long piece of debris from a recent Chinese anti-satellite test that was predicted to pass 1.7 miles in front of the space shuttle. While the debris required close monitoring, the astronauts were not required to carry out any avoidance maneuvers.

But the debris risk is real and LeRoy Cain, chairman of NASA's Mission Management Team, said sensors in the wing leading edge system recorded a presumed space debris impact earlier, on panel No. 11 on Atlantis' right wing. But the magnitude of the impact was an order of magnitude below the threshold that could cause noticeable damage.

"You know we have the wing leading edge impact indication system that we have turned on to monitor for any kind of MMOD (micrometeoroid/orbital debris) or other impacts we might have during the on-orbit phase," Cain said. "It did register an impact, or indications or an impact, on the right-hand side, on panel 11R of the reinforced carbon carbon part of the wing leading edge.

"The indication was .47 Gs. The team evaluated it through the normal screening process. We do think, by all indications as far as we can tell, we do think it's probably a real indication of an impact. ... We're not concerned that it's done any kind of damage that would be any concern to us, certainly not critical damage. We think if anything, just very, very small coating damage. We'll get a look at this area again when we do a late inspection (near the end of the mission) in any case. But this is not an indication we're concerned about at this time."

Asked what sorts of forces would cause real damage for a wing leading edge panel, Cain said "there are many, many different variables. But we're talking, generally speaking, in a number of Gs. This is less than .5 Gs. It's, generally speaking, an order of magnitude greater than what we're seeing here."

During initial inspections of the shuttle's heat shield Tuesday, the Atlantis astronauts downlinked images showing minor tile damage on the shuttle's right wing. Engineers decided Tuesday night the damage was of no consequence and would not require an additional, focused inspection.

"The team came back today and we have essentially cleared all of the TPS (thermal protection system) for the tiles and for the blankets," Cain said. "So essentially, all the TPS save for the RCC (reinforced carbon carbon) we've cleared for entry. We've also said we don't need any focused inspection for any of the TPS."

Shortly after Cain's briefing, the reinforced carbon carbon nose cap and wing leading edge panels were cleared as well.

The only other issue of note, Cain said, was photography showing a fine particulate dusting a handrail and insulation blankets on a carrier box housing the new Wide Field Camera 3 that will be installed in the Hubble Space Telescope during a spacewalk Thursday.

Cain said the white power-like substance was not present before launch and may be some sort of material that shook loose from payload bay bulkhead insulation blankets during the climb to space. Because of concern about possible contamination of the new camera, Cain said the spacewalkers would take extra care to avoid the dust when the camera is removed from its case Thursday.


01:45 PM, 5/13/09, Update: Shuttle Atlantis grapples Hubble Space Telescope (UPDATED at 6:05 PM with mission, post-management team briefings)

Editor's note...
A separate story will be posted shortly to discuss the status of Atlantis' heat shield. LeRoy Cain, chairman of NASA's Mission Management Team, said the shuttle's heat shield tiles and blankets have been cleared for entry as is. Analysis of the ship's nose cap and wing leading edge panels is not yet complete, but Cain said he does not anticipate any problems based on results to date. Other topics covered in today's briefing include an apparent wing leading edge impact by space debris that was detected by sensors in the past 24 hours. Cain said the magnitude of the strike was an order of magnitude less than the force required to cause damage.

The Hubble Space Telescope, hobbled by old age and years of post-Columbia neglect, was plucked out of open space by the crew of the shuttle Atlantis today, setting the stage for a final five-spacewalk overhaul to give the iconic observatory an extended lease on life.

Commander Scott Altman, who flew an F-14 jet in the movie "Top Gun," deftly maneuvered the orbiter to within a few dozen feet of the 24,500-pound telescope as the two spacecraft sailed through space in lockstep, covering 84 football fields per second 350 miles above western Australia.

Astronaut Megan McArthur, operating the shuttle's 50-foot-long robot arm with easy grace, then grappled the huge observatory at 1:14 p.m. to wrap up a two-day rendezvous.

"Houston, Atlantis, Hubble has arrived on board," Altman exclaimed.

"Atlantis, Houston, we copy. Nice job, Megan, nice job on the prox ops flying as well," astronaut Dan Burbank replied from mission control. "It's great to be back with the telescope."

"Thank you, Houston, appreciate the support getting us here," Altman said.

Added lead spacewalker self-described "Hubble hugger" John Grunsfeld: "We're very excited up here, I can tell you."

The Hubble Space Telescope on the end of the shuttle Atlantis'
robot arm shortly after capture
(Photo: NASA TV)

The only problems during today's approach was a glitch with a communications unit aboard Atlantis designed to relay commands to the telescope from Hubble engineers on the ground. As it turned out, the equipment was working properly, but the engineers were attempting to send commands at a higher-than-allowed data rate. The commands were sent through a NASA satellite instead and the astronauts easily compensated for a minor delay that resulted in a slight misalignment between the two spacecraft.

After confirming final commands had, in fact, reached the telescope, McArthur was cleared to mount Hubble on a rotating service platform at the back of Atlantis' payload bay. Once locked in place, the astronauts carried out a detailed photo survey to document the condition of Hubble's protective insulation and to look for signs of impact damage from micrometeoroids and space debris.

An electrical cable in the servicing platform was remotely extended and plugged into a receptacle at the base of the telescope to provide shuttle power for the duration of the overhaul.

"We'd like to congratulate you on a great job today with the rendezvous, the grapple and the berth," Burbank radioed at the end of his shift. "It's wonderful to see Hubble safely aboard Atlantis and we're all looking forward very much to a couple of great days of EVA."

"Hey Dan, to you, Tony (Ceccacci, lead flight director), the entire team ... we just want to say thanks for all the work that got us to this point," Altman said. "We realize we're just setting the stage for the main activity, doing the repairs on Hubble, but you've got to get past step one to get any further along and having Hubble safely berthed in the bay feels great to us. Thanks to you all, it was a team effort, and we appreciate the help."

Seen for the first time since a pre-Columbia service call in early 2002, the space telescope appeared to be in remarkably good condition given its 19 years in the harsh environment of space, with no immediately obvious problems with its insulation panels or other exterior components.

"Just looking out the window here, and it's an unbelievably beautiful sight, amazingly, the exterior of Hubble, an old man of 19 years in space, still looks in fantastic shape," Grunsfeld radioed.

But Hubble Program Manager Preston Burch said appearances could be deceiving.

"As we approached Hubble, the location of the grapple, we're only looking at one side of it and that's the side that never sees the sun," he said. "That's the side that has the least amount of degradation and the side we would expect to be in the best condition. When we go around to the other side, we can logically expect substantially more deterioration."

The first of five back-to-back spacewalks is on tap Thursday, starting around 8:16 a.m. Over the course of the mission, the astronauts plan to install two new science instruments, repair two others, swap out a science data computer and install new batteries, gyroscopes, a refurbished fine guidance sensor and new insulation panels.

The goal is to extend Hubble's life by at least five years.

"We're very much looking forward to getting on with these EVA activities," said Jon Morse, director of astrophysics at NASA headquarters. "I wanted to note that when we first had the image of HST on the big screen in our control room, there were audible gasps of elation that this was truly a wonderful sight seven years or so after the last servicing mission, to see the space telescope. ... After 19 years, it still looks to be in fantastic shape. So we're really looking forward to tomorrow and getting on with the instrument upgrades and repairs."


10:50 AM, 5/13/09, Update: Shuttle enters final stages of Hubble rendezvous

Trailing the Hubble Space Telescope by about 50,000 feet, commander Scott Altman fired the shuttle Atlantis' left-side orbital maneuvering system rocket at 10:41 a.m. to kick off the terminal phase of a complex procedure to catch up with the observatory for a fifth and final service call.

The terminal initiation, or TI, burn lasted 12 seconds and changed the shuttle's velocity by 9.8 feet per second, putting Atlantis in a near-circular orbit at an altitude of 349 miles.

"Good burn, no further trim required," astronaut Dan Burbank radioed from mission control.

Mission control plot showing Atlantis' trajectory as it begins the
terminal phase of today's rendezvous (Photo: NASA TV)

Over the next two hours, Altman will make course corrections as needed to reach a point about 700 feet below the bus-size space telescope as both spacecraft streak through space at 5 miles per second.

At that point, Altman will take over manual control of the shuttle and guide the ship up to within a few dozen feet of the observatory. Megan McArthur, operating Atlantis' 50-foot-robot arm, plans to grapple the telescope at 12:54 p.m. and mount it on a service platform in the shuttle's cargo bay.


06:40 AM, 5/13/09, Update: Atlantis closes in on Hubble Space Telescope

In the final stages of a complex rendezvous, the shuttle Atlantis closed in on the Hubble Space Telescope today, on track for a robot arm capture that will set the stage for a challenging five-spacewalk service call. Astronaut Megan McArthur, operating the shuttle's 50-foot-long space crane, plans to grapple the telescope around 12:54 p.m. and then mount it on a service platform at the back of Atlantis' payload bay.

Late Tuesday, Hubble's aperture door was closed and early today, it's twin high-gain antennas were retracted to prepare the observatory for capture.

The terminal phase of the rendezvous begins at 10:41 a.m. with a critical rocket firing designed to close the final few miles between the shuttle and the bus-size space telescope. Commander Scott Altman, flying Atlantis from the ship's aft flight deck, plans to approach the observatory from below, matching velocities as the two spacecraft steak 340 miles above the north coast of Madagascar at 5 miles per second (interested readers and check on the location of the shuttle and Hubble with GoogleSatTrack at: http://www.lizard-tail.com/isana/tracking/

"Rendezvousing with Hubble is a little different than going to space station," Altman said in a NASA interview. "Obviously, it's in a different orbit, but it's also a small target compared to how big station has gotten, and it doesn't help us out as much during the rendezvous in that station has a little system that gives it range and range rate as you get close. Hubble is just passive, it's sitting there, it doesn't have reflectors. So we're using a little handheld laser, which is kind of like a police radar gun that you would see on the side of the road, to get the distance and the closing rate as we're coming up to Hubble. We're doing it basically by hand."

In the final phases of the approach, "I'm looking out the window, watching Hubble, and then listening to the calls that my other operators are making by using that laser range finder about how close we are and how fast we're going to know what input to make as we get close to it. So I think it's a more challenging rendezvous than having as much information as the station guys have."

This is Altman's second Hubble visit in a row and "at one point last mission we talked about putting a reflector on Hubble to make it easier for the next guy, but I thought, well, you know, it was hard for me; let it be as hard for the next guy. Now it turns out I am the next guy so I realize that was shortsighted of me!

Once Atlantis closes to within a few feet of Hubble, Altman will fly in formation with the telescope to give McArthur a stable target.

"If I've done my part well and flown up to Hubble gracefully, I can stop and I say, OK, I'm going to go to free drift, which means I'm not making any more inputs, and that we'll stay close together without much motion to make it easier for her to reach out and grab it. We also train to grab it if it's moving a little bit but my job is to make it as stable and easy as possible for the arm operator to go out and get."

McArthur, making her first space flight, said she doesn't anticipate any problems.

"As soon as we're comfortable that the orbiter's rate has been matched to the telescope and the telescope looks to me like it's stable and not moving, then I take the robotic arm, the shuttle's robotic arm, and I reach out and grab the telescope," she said in a NASA interview. "There is a grapple fixture, a pin, basically, on the side of the telescope, that we use. The robotic arm grabs onto that. Once we have a good capture of the telescope, I then maneuver the robotic arm, to install the telescope into a berthing mechanism at the back end of the shuttle payload bay. And once we have installed the telescope in that berthing mechanism, we latch it down and I can release the shuttle's robotic arm."

Hubble will be mounted on a rotating service platform that can position the telescope as required for servicing. A detailed photo survey will be carried out shortly after capture to document the condition of Hubble's exterior and its aging insulation and an electrical cable will be remotely plugged to provide shuttle power for the duration of the service call.

Engineers are anxious to get a good look at Hubble's insulation to find out how it may have degraded over the seven years since the last shuttle visit in 2002.

"When we arrive, I expect it not to look a lot different than it did on STS-109 (in 2002), but I do expect that ... some of the multi-layer insulation on the outside of the telescope will be peeled back a little bit more," lead spacewalker John Grunsfeld, making his third visit to Hubble, said before launch.

"The environment where Hubble is is pretty severe, the temperature extremes, atomic oxygen, the solar ultraviolet, all those nasty things in space are what is causing the telescope (exterior) to degrade. It's somewhat expected. Hubble has been in space for (19) years, it's pretty remarkable it's doing as well as it has. What I remember so vividly from the last missions is that once you open up the inside of the telescope, it looks absolutely brand new. We expect that to be the case as well."

The astronauts will review spacewalk procedures late this afternoon before going to bed at 8:31 p.m. Grunsfeld and Andrew Feustel plan to begin the mission's first EVA at 8:16 a.m. Thursday.

Here is an updated timeline of today's activity (in EDT and mission elapsed time; includes revision B of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05/13/09
05:01 AM...01...15...00...Crew wakeup
06:16 AM...01...16...15...HST: High gain antenna retraction
07:26 AM...01...17...25...Group B computer powerup
07:41 AM...01...17...40...Rendezvous operations timeline begins
08:11 AM...01...18...10...Middeck preps
08:41 AM...01...18...40...EVA-1; Tools configured
08:51 AM...01...18...50...HST: Solar arrays slewed to 90 degrees
09:02 AM...01...19...01...NC-4 rendezvous rocket firing
10:41 AM...01...20...40...TI rendezvous rocket firing
12:01 PM...01...22...00...HST: Move to capture attitude
12:54 PM...01...22...53...HST capture
01:46 PM...01...23...45...HST berthing
02:01 PM...02...00...00...HST survey
02:16 PM...02...00...15...External power on
02:46 PM...02...00...45...Group B power down
03:56 PM...02...01...55...Shuttle robot arm (SRMS) park
04:00 PM...02...01...59...Mission status briefing on NTV
04:21 PM...02...02...20...HST: Solar arrays slewed to 0 degrees
04:41 PM...02...02...40...EVA-1: Procedures review
05:41 PM...02...03...40...HDTV downlink
08:31 PM...02...06...30...Crew sleep begins
08:31 PM...02...06...30...HST: KU-band checkout
08:45 PM...02...06...44...Space telescope update
09:00 PM...02...06...59...Daily video highlights reel on NTV
10:01 PM...02...08...00...HST: Engineering data playback


11:00 PM, 5/12/09, Update: NASA rules out focused inspection of damaged tiles

After additional analysis, engineers concluded Tuesday that damaged heat shield tiles on the shuttle Atlantis' right wing do not require any additional "focused" inspections to collect additional data.

While a review of heat shield inspection photos and data is not yet complete, flight controllers told the Atlantis astronauts they would not have to conduct any additional inspections of the damaged tiles in question.

"And Scooter, also I've got some good news about the tile damage that we saw on the starboard chine area earlier today," astronaut Alan Poindexter radioed from mission control shortly after 8 p.m.

"Oh, I'm looking forward to that. Go ahead," replied shuttle commander Scott "Scooter" Altman.

"It turns out that a focussed inspection of that area on the starboard chine is not going to be required," Poindexter reported.

"All right, you've got some happy EVA campers on that," Altman said.

"Again, that's just for that area," Poindexter said. "We're going to look at the rest of the data you sent down throughout the evening and into tomorrow and we'll have further words on focused inspection down the road a little bit."

The astronauts spent most of the day Tuesday conducting a detailed heat shield inspection using an instrumented boom on the end of the shuttle's robot arm. The only obvious signs of damage were a handful of chipped tiles on the front portion of the right wing that apparently were struck by debris about 106 seconds after liftoff Monday.

The dings and nicks did not appear serious and while a focused inspection could still be ordered for some other area of the spacecraft if additional damage is spotted, Poindexter's report was welcome news for Altman and his six crewmates.


2:21 PM, 5/12/09, Update: Atlantis tile damage assessed; initial indications not serious, but analysis not yet complete (UPDATED at 3:23 p.m. with photographs, comments from flight director; UPDATED at 7:15 p.m. with post-MMT briefing)

Engineers at the Johnson Space Center are evaluating a small area of tile damage on the forward part of the shuttle Atlantis' right wing where it joins the ship's fuselage. The nicked tiles, apparently damaged during launch by a debris impact around 106 seconds after liftoff, were spotted during a lengthy heat shield inspection by the Atlantis astronauts.

LeRoy Cain, chairman of NASA's Mission Management Team, told reporters late Tuesday engineers are not overly concerned about the damage and probably will not require an additional, "focused" inspection to collect more data. But engineers will continue their assessment overnight to make sure the damage poses no risk to the shuttle.

"This area is about 21 inches long," Cain said, describing a photograph of the damage site. "It looks like something just kind of chattered down along that edge there on the starboard chine area. The preliminary indications are that the damage is not very deep here, it's not very significant. This is not something we're very concerned about. But we want the team to do our normal assessment and evaluation of it, and they'll do that overnight tonight."

Tile damage observed during heat shield inspection
(Photo: NASA TV via Spaceflightnow.com)

But Cain said the preliminary assessment "certainly doesn't look like it's going to be an issue for us. And matter of fact, the teams are saying we probably will not even need a focused inspection in this area. But ... we want to take the time and review the data overnight."

If a focused inspection is required, it would be carried out Friday, before the crew's second Hubble Space Telescope servicing spacewalk gets under way. Lead flight director Tony Ceccacci said a focused inspection, if ordered, would have no major impact on the planned EVA.

At the Kennedy Space Center, meanwhile, engineers are evaluating damage to the flame deflector at launch pad 39A where Atlantis began it's voyage Monday. The flame deflector, positioned directly below the exhaust ports of the shuttle's mobile launch platform, suffered significant erosion of the heat-resistant Fondu Fyre coating used to deflect 5,000-degree flame from the shuttle's solid-fuel boosters.

Engineers found a fair amount of debris littering the pad surface and the immediate area around the "flame trench" during a post-launch inspection, but "this was all debris that was moving around in the area that was below the pad area where the vehicle sits on top," Cain said. "Atlantis was not in danger of being struck by this debris."

The shuttle Endeavour currently is mounted on nearby launch pad 39B where it is on stand-by duty for a possible emergency rescue mission in case the Atlantis astronauts encounter any major problems in orbit that might prevent a safe re-entry. Engineers plan to move Endeavour to pad 39A for launch June 13 on a space station assembly mission after it is released from rescue standby.

Cain said the damage to the flame deflector at pad 39A does not appear to be serious and engineers are confident it can be repaired with no impact on Endeavour's June launch date.

Damage to pad 39A was not the only issue engineers at Kennedy had to deal with. A few hours after pad 39A was blasted by Atlantis' exhaust, two lightning strikes were recorded at pad 39B.

"The weather apparently got a little stirred up last night and there was some lightning and some storms in the area in the vicinity of the cape and the pads," Cain said. "And we did record two lightning strikes at pad B."

Engineers are carrying out an assessment to make sure the strikes caused no problems for the shuttle's complex electrical system.

The heat shield damage on Atlantis' right wing was spotted during an all-day inspection using the shuttle's robot arm and a 50-foot-long instrumented extension boom. Astronaut Dan Burbank in mission control at the Johnson Space Center in Houston, told the astronauts the damage did not appear serious, but the assessment was not yet complete.

Debris just before impact on the shuttle Atlantis' right wing chine area.
(Photo: NASA TV via Spaceflightnow.com)

Debris impacting the shuttle Atlantis' right wing chine area.
(Photo: NASA TV via Spaceflightnow.com)

"Just want to let you know that during the starboard (wing) survey, LDRI survey, in the chine area there is a stretch of about 21 inches, four or five tiles that show some nick damage it looks like," Burbank said. "It probably was debris related. The ascent imagery folks have gone back and looked at the imagery and there was an event at about 104 seconds or so that was in that area that might correspond to what we saw there.

"At this point, the preliminary assessment is it doesn't look very serious, those tiles are pretty thick, the nicks looks to be pretty small," he said. "It's probably too early to say we'd be looking at a focused inspection, but we are at this point discussing possibly having to get back into the ET (external tank) umbilical imagery downlink procedure sometime later here to see if we can get some more information on the debris."

Burbank was referring to a camera in the belly of the shuttle that took photographs of the shuttle's external tank after it was jettisoned following launch Monday. The photos might show where the debris originated, but the astronauts have had problems electronically retrieving the stored pictures.

"OK, that makes sense,It sounds like there may be more value in that than we thought," commander Scott Altman replied. "Let us know, we'll try and work that, although the indications weren't looking very promising."

"Discovery, copy, and we understand as well," Burbank said. "We'll get some pictures and some charts and send them up to you so that you've got all the information we've got. But again, right now everybody's feeling pretty good it's not something particularly serious. We just want to make sure we do the right thing and complete all the analysis."

"Roger that, Houston," Altman said. "We know it takes a while to put the story together. Appreciate that due diligence in working that. We'll try to give you whatever data we can. Hopefully, the HD video and the stills would help with the analysis as well."

"OK, that sounds good," Burbank said. "One other piece of this. Also in the wing leading edge sensor data, that inboard-most sensor in the starboard wing showed evidence of a hit of about 2.9 GRMS at about the 104, 106 second timeframe, too. So all of these seem to latch up pretty cleanly in the preliminary data."

"OK, copy that," Altman said. "We'll stand by for further words."


12:10 PM, 5/12/09, Update: Booster flame deflector damaged during Atlantis launch; no impact expected on June mission

The massive flame deflector below the shuttle Atlantis' mobile launch platform was damaged during liftoff Monday, but officials said Tuesday a preliminary assessment indicates no impact on plans to launch the shuttle Endeavour from the same pad on June 13.

"The SRB flame deflector, there's about a 25-square-foot area on the north side where (a heat resistant coating) came off," a NASA spokeswoman said. "They had some pneumatic lines that were damaged."

While inspections are still in progress, she said, "right now, they don't see any indications there will be an impact on the June launch."

NASA's shuttle launch pads feature a so-called "flame trench" and a massive deflector that channels main engine exhaust to one side and solid-fuel booster exhaust to the other. During launch of shuttle mission STS-124 last May, the flame trench at launch pad 39A suffered extensive damage when bricks were blasted away from the walls during booster ignition.

Following Atlantis liftoff, engineers found heat-resistant fondu fyre debris from the flame deflector littering the northeast pad surface, a valve complex in the pad's sound suppression water system and near the perimeter fence. Inspections are continuing.

Endeavour currently is mounted on launch pad 39B where it is on stand-by duty for a possible emergency rescue mission in case the Atlantis astronauts encounter any major problems in orbit that might prevent a safe re-entry. Engineers plan to move Endeavour to pad 39A for launch June 13 on a space station assembly mission after it is released from rescue standby.


7:25 AM, 5/12/09, Update: Astronauts gear up for heat shield inspection; prep for Hubble rendezvous

The Atlantis astronauts were awakened at 5:01 a.m. Tuesday to kick off a busy day of heat shield inspections, spacesuit checkouts, tool preps and rendezvous rocket firings to fine tune the shuttle's approach to the Hubble Space Telescope. If all goes well, commander Scott Altman will position Atlantis directly below the bus-size observatory just before 1 p.m. Wednesday so Megan McArthur, operating the shuttle's robot arm, can pluck the telescope out of open space and mount it in the ship's cargo bay for servicing.

But first, the astronauts must complete a detailed checkout of Atlantis' heat shield, using the robot arm and a 50-foot instrumented extension to examine the ship's reinforced carbon carbon nose cap, RCC wing leading edge panels and protective tiles across the shuttle's belly.

The post-Columbia procedure has been modified for Atlantis' mission because the astronauts cannot take advantage of the International Space Station's crew to help inspect the heat shield. And, of course, the station is not available to Altman's crew for "safe haven" if any problems are discovered that might prevent a safe re-entry.

To protect against such worst-case scenarios, a second shuttle - Endeavour - is being prepped for launch to rescue the Atlantis astronauts if necessary, eliminating the need for safe haven aboard the space station.

To make up for the lost space station inspections, the Atlantis astronauts are using a modified inspection plan that will duplicate, if not exceed, the thoroughness of the space station procedure.

Late Monday, shortly after reaching orbit, the crew used the robot arm to inspect the payload bay and the shuttle's upper crew cabin exterior.

"What we're going to do on flight day two is, we added in a belly tile survey," said flight director Tony Ceccacci. "It's an additional two hours 10 minutes of survey ops. ... They've developed the survey that meets all the required detection requirements. So what we'll wind up doing is we'll be doing the starboard wing leading edge and there's a point where we break out of that and then do starboard part of the belly. That takes about 30 minutes or so there.

"After we finish the belly up, that starboard belly portion, we'll go ahead and finish up the starboard wing leading edge, go ahead and do the nose cap after that and then go to the port wing leading edge. And there's a point in there that we break out and do about 96 minutes of belly survey. Then after that, we go back into the port wing leading edge survey and get that done and then we're done for the day."

During space station flights, approaching shuttle's pause just below the lab complex and carry out a slow back-flip maneuver, exposing the belly of the ship to the station crew for a detailed photo survey using 400-mm and 800-mm lenses. The additional belly tile surveys added to the Atlantis timeline will make up for the station procedure and give engineers just as much, or more, data on the health of the heat shield than they get from a station flight.

The rendezvous pitch maneuver is carried out early in a mission and as such, only provides insight into ascent debris damage. The primary threat for the Atlantis astronauts, given the new techniques that duplicate what is normally achieved with the RPM, is impacts from space debris and micrometeoroids. The space station orbits at an altitude of about 220 miles while Hubble circles the globe at an altitude of 350 miles. The space debris environment - bits of junk from old satellites and rocket bodies - is worse at Hubble's altitude than the station's.

"Remember now, the RPM, it's prime purpose is to inspect the bottom of the vehicle for ascent debris damage," said Paul Hill, director of mission operations at the Johnson Space Center. "What we have more of on HST is statistically higher risk of orbital debris because of the higher altitude. So the RPM really isn't designed or placed in the mission to catch that. That's more of a long-duration thing and our greater concern for that kind of damage we pick up with the late inspection."

The late inspection will be carried out after the Hubble Space Telescope is re-deployed to look for any signs of damage that might have occurred since the post-launch inspections.

Engineers plan to complete their initial assessment of ascent imagery and the results of the crew's post-launch inspections by late Wednesday to determine the overall health of the thermal protection system and whether a more detailed "focused" inspection might be needed later to examine any trouble spots.

No obvious problems were seen during launch Monday and flight controllers say Atlantis appears to be in excellent health. Even so, engineers at the Kennedy Space Center are continuing to process Endeavour for a possible rescue flight if needed. Launch director Mike Leinbach said the goal is to get Endeavour ready for the start of a three-day countdown and then to hold there while Atlantis' mission proceeds.

Here is an updated timeline of today's activity (in EDT and mission elapsed time; includes revision B of the NASA television schedule):

EDT........DD...HH...MM...EVENT

05/12/09
Tue 05:01 AM...00...15...00...Crew wakeup
Tue 06:26 AM...00...16...25...NC-2 rendezvous rocket firing
Tue 07:01 AM...00...17...00...Shuttle arm (SRMS) unberths inspection boom (OBSS)
Tue 07:36 AM...00...17...35...Airlock prepped
Tue 08:16 AM...00...18...15...Flight support structure prepped
Tue 08:26 AM...00...18...25...Spacesuit checkout
Tue 09:01 AM...00...19...00...Starboard RCC survey
Tue 09:41 AM...00...19...40...Spacesuit swap
Tue 09:51 AM...00...19...50...Starboard belly tile survey
Tue 10:11 AM...00...20...10...Spacesuit checkout
Tue 10:16 AM...00...20...15...Starboard wing RCC survey
Tue 10:26 AM...00...20...25...Crew meals begin
Tue 11:31 AM...00...21...30...Nose cap survey
Tue 12:21 PM...00...22...20...Port wing RCC survey
Tue 12:36 PM...00...22...35...REBA checkout
Tue 01:06 PM...00...23...05...EVA tool unstow/config
Tue 01:11 PM...00...23...10...Port belly tile survey
Tue 01:31 PM...00...23...30...10.2 psi depressurization
Tue 02:26 PM...01...00...25...Ergometer setup
Tue 02:30 PM...01...00...29...Mission status briefing on NTV
Tue 02:31 PM...01...00...30...HST: Solid state recorder playback
Tue 03:06 PM...01...01...05...Port wing RCC survey
Tue 03:23 PM...01...01...22...Progress 33 docking with space station on NTV
Tue 04:06 PM...01...02...05...T-0 umbilical survey
Tue 04:21 PM...01...02...20...OBSS berthing
Tue 05:00 PM...01...02...59...Post-management team briefing on NTV 
Tue 05:21 PM...01...03...20...FCMS ops
Tue 05:36 PM...01...03...35...OMS pod survey
Tue 05:51 PM...01...03...50...Rendezvous tools checkout
Tue 05:51 PM...01...03...50...Laser scan data downlink
Tue 06:01 PM...01...04...00...HST: Aperture door closed
Tue 06:41 PM...01...04...40...NC-3 rendezvous rocket firing
Tue 08:36 PM...01...06...35...HST: Maneuver to rendezvous attitude
Tue 09:01 PM...01...07...00...Crew sleep begins
Tue 09:01 PM...01...07...00...HST: Low-gain direct to TDRS
Tue 09:26 PM...01...07...25...HST: 3 gyro ops reconfig
Tue 09:30 PM...01...07...29...Space telescope operations update on NTV
Tue 10:00 PM...01...07...59...Daily highlights reel on NTV


5:30 PM, 5/11/09, Update: Shuttle in good shape after launch; no signs of impact damage; initial post-launch inspections on tap

The shuttle Atlantis came through it's ground-shaking launch and high-speed climb to orbit in good shape Monday with no obvious signs of any significant debris strikes or other problems, officials said.

"At this point, there's absolutely no imagery observations indicating any concern at all," astronaut Greg H. Johnson radioed Atlantis from mission control in Houston.

"That's outstanding, Houston," commander Scott Altman replied from Atlantis. "Thanks for that early word."

Mike Moses, chairman of NASA's mission management team at the Kennedy Space Center, said even though engineers saw "nothing of note" in the ascent imagery, "we'll let the teams do all the right thingsŇ and go off and talk and review all the data. We'll inspect the vehicle in the next several days to make sure we came out of ascent clean."

Flight controllers hope to have a preliminary assessment of the health of the shuttle's heat shield by Wednesday evening, before the a spacewalk Thursday to begin refurbishing the Hubble Space Telescope.

Otherwise, Moses said, Atlantis came through launch in good shape despite alarms that sounded early in the climb to space and a possible short in a subsystem.

"There were a couple of issues when we lifted off," Moses said. "Right away off the pad,, ASA-1 (aerosurface actuator 1), which is a flight control feedback system that controls the aerosurfaces, all the TVCs (thrust vector controllers), it's one of four systems and it failed.

"It looks like the power failed to that unit and took it down. Again, it was one of four, it was no issue, it bypassed itself. The crew's going to leave it alone for now while the teams look at it. We don't need it again until entry, obviously, so we'll do a thorough data review to find out what really happened to that box and whether we can reset it or not. Again, there's no real rush, there's no impact to that box being down.

"The other nuisance, on the left main engine there was a hydrogen-out pressure (signal) basically that was flashing transient, it kind of changed its signature on us," Moses said. "When it tripped the limit, it rang an alarm on board and I think it did that two or three times on the way uphill. It's just a transient 'ducer, it's there for awareness, it didn't feed into any software, it wasn't part of any control loop. So no impact at all to the main engines or their performance."

With ascent behind them, Altman and his crewmates turned their attention to setting up the shuttle's on-orbit computer network and checking out the ship's robot arm for an evening inspection of the payload bay and the upper surfaces of the crew module. The astronauts also plan to check out the flight support system cradle at the back of the cargo bay that will be used to hold Hubble in place after the telescope is captured Wednesday.

Crew sleep is scheduled to begin at 9:01 p.m.


02:30 PM, 5/11/09, Update: Shuttle Atlantis launches on Hubble servicing mission

With a second shuttle on standby for possible rescue duty, the shuttle Atlantis blasted off Monday on a high-stakes five-spacewalk mission to resuscitate the aging Hubble Space Telescope, a fifth and final housecall to give the hobbled satellite a new lease on life.

With its three main engines roaring at full throttle, Atlantis' twin solid-fuel boosters ignited with a ground-shaking roar at 2:01:56 p.m., instantly pushing the winged spacecraft skyward atop a churning cloud of exhaust.

Shuttle Atlantis' main engines throttle up for launch

At the moment of liftoff, the Hubble Space Telescope was soaring high above central Florida in its 350-mile-high orbit, streaking through space at 5 miles per second. But it will take Atlantis two days to catch up with the observatory to kick off the long-awaited repairs.

Quickly climbing above its launch gantry, Atlantis wheeled about and arced away to the East over the Atlantic Ocean, leaving a trail of smoke in its wake as it rocketed through a partly cloudy sky.

At the controls aboard Atlantis were commander Scott Altman, pilot Gregory C. Johnson and flight engineer Megan McArthur. They were joined by spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good. It will be the second Hubble visit in a row for Altman and Massimino and the third for Grunsfeld. The rest are shuttle rookies.

The Hubble mission is the only flight on NASA's post-Columbia manifest that does not go to the International Space Station. Because Hubble and the space station are in different orbits, Altman and his crewmates cannot seek safe haven aboard the lab complex if any major problems prevent a safe re-entry.

Atlantis climbs toward space

In addition, at Hubble's higher altitude the risk of a catastrophic impact with space debris is greater, on average 1-in-229 compared to less than 1-in-300 or better for a typical station mission. As a result, the shuttle Endeavour is poised atop launch pad 39B, on stand by for possible rescue duty if needed. Over the next four days, engineers will get Endeavour ready for the start of a three-day countdown and then stand by as Atlantis' mission proceeds.

If any ascent-related heat-shield damage is spotted, Endeavour could, in theory, be ready for launch by next Monday. If impact damage from space debris is seen toward the end of the mission, Endeavour could be launched on three days notice.

While it will take several days to complete an initial inspection of Atlantis' heat shield, there were no obvious debris strikes or other problems visible in television views downlinked from a camera on the side of the shuttle's external tank during the critical first two minutes of flight.

NASA managers are confident Endeavour won't be needed, thanks to post-Columbia improvements that have greatly reduced foam shedding from the shuttle's external tank and development of repair techniques that can fix the sort of damage that might be reasonably expected. Endeavour is on stand by for the remote possibility of Columbia-class damage.

"There are very small odds we would, in fact, have a problem on ascent for which the remedy would be a launch on need shuttle, a rescue shuttle," said former NASA Administrator Mike Griffin, the man who approved the Hubble servicing mission. "But against the very small probability that it could occur, we will carry that rescue option in the manifest. ... The safety of our crew conducting this mission will be as much as we can possibly do."

Griffin's predecessor, Sean O'Keefe, canceled the final Hubble servicing mission in 2004 because of post-Columbia safety concerns. O'Keefe told CBS News Monday he did not regret the decision, based on the state of post-Columbia safety upgrades at the time, but added he was "thrilled and delighted" the mission had been reinstated.

"Absolutely no regrets whatsoever, in January of '04, but extraordinary pride in the colleagues here at NASA who really put an awful lot of determination, persistence, talent and technical expertise to bear to make this day possible," he said.

Launch originally was scheduled for last Oct. 14, but just three weeks before takeoff a critical circuit in the telescope's science instrument data system malfunctioned. To restore full redundancy, NASA managers decided to delay the servicing mission to give engineers time to check out and certify a flight spare that had been used for ground testing. The replacement computer was delivered to the Kennedy Space Center on March 30 and launched aboard Atlantis.

Hoping to extend Hubble's life well into the next decade, the four spacewalkers, working in two-man teams, plan five back-to-back excursions to install six new stabilizing gyroscopes, six new nickel-hydrogen battery packs, the new data computer and two new instruments, the $126 million Wide Field Camera 3 and the $81 million Cosmic Origins Spectrograph. Like all modern Hubble instruments, both are equipped with corrective optics to counteract the spherical aberration that prevents Hubble's 94.5-inch mirror from achieving a sharp focus.

The Florida coast drops away as Atlantis climbs toward space

The Atlantis astronauts also will attempt to repair two other instruments: the Space Telescope Imaging Spectrograph, which suffered a power supply failure in 2004, and the Advanced Camera for Surveys, which broke down in 2007. Neither instrument was designed to be serviced in orbit, but determined engineers devised custom tools and an ingenious plan for the spacewalkers to bypass the failed electronics.

If the instrument repairs go well, the astronauts will install an upgraded fine guidance sensor during the final spacewalk. If the astronauts have problems with the repair work, the guidance sensor task likely will be deleted to give the crew more time to complete at least one of the repairs.

Either way, the astronauts plan to install new insulation and a grapple fixture that will permit attachment of a rocket motor or even NASA's new Orion manned spacecraft in the future to drive Hubble out of orbit when it is no longer able to do science.

"On Servicing Mission 4, we're going to give Hubble another extreme makeover," said Program Manager Preston Burch. "This makeover will be the best one yet because we will outfit Hubble with the most powerful and advanced imaging and spectrographic instruments available and we will extend Hubble's operating lifetime for five additional years."

Without Servicing Mission 4, engineers believe Hubble would be hard pressed to survive past 2010. But if the Atlantis astronauts are successful, they will leave behind an essentially new telescope, one that is equipped with a full suite of five operational scientific instruments for the first time since launch in 1990. And with new gyros and batteries, Hubble has a good chance of remaining fully operational long enough to work in concert with its eventual replacement, the James Webb Space Telescope.

"There's not much margin for error," Burch said Sunday. "We'll need flawless execution from our astronaut team and we'll also need flawless performance from all of our hardware. But we have done extensive testing, extensive training and we're highly confident that we're going to have another successful mission like the ones we've had before."

NASA has spent about $10 billion on the Hubble Space Telescope to date, making it one of the most expensive science projects in history. The cost of the Atlantis mission and the two new instruments totals $887 million.

Asked whether it made sense to spend more money on a 20-year-old space telescope, Griffin said it makes all the sense in the world.

"After we get done with it, it's not an old telescope," he told CBS News in a recent interview. "Every subsystem that needs refurbishment is being refurbished and it's getting a new complement of instruments. So the only part of it that's old is the optical metering structure and the glass. And the glass doesn't care. When they're done, it really is not an old telescope, it's a new telescope."

"So the question you want to ask yourself when you look at the value proposition, if for the cost of this shuttle flight - and bear in mind, most of the instrument costs and all that were already paid for - plus the team that we've been carrying, and it's about a $10-million-a-month team, if for whatever all that adds up to you could get yourself a new telescope in space, would you think that would be worthwhile? And I think most people, most astronomers, would say yes."


11:30 AM, 5/11/09, Update: Shuttle fueling complete; crew straps in

The shuttle Atlantis' external tank was loaded with a half-million gallons of supercold liquid oxygen and hydrogen rocket fuel early Monday and the ship's seven-member crew began strapping in at 10:44 a.m. to await launch on a mission to service the Hubble Space Telescope.

There are no technical problems at launch complex 39A and forecasters are predicting good weather during the shuttle's 62-minute launch window. Liftoff is targeted for 2:01:56 a.m., 20 minutes after the opening of the window to improve ascent performance and to provide additional time to assess potential close encounters with space debris and other satellites.

Shuttle pilot Gregory C. Johnson straps in for launch

There are three collision avoidance windows during which Atlantis cannot take off, two because of possible close encounters with a Russian Progress supply ship and the third because of the International Space Station. If Atlantis takes off on time, the windows are a moot point. But for the record, they are (in EDT):

  1. 2:08:41 PM to 2:11:35 PM
  2. 2:19:37 PM to 2:20:38 PM
  3. 2:21:43 PM to 2:22:55 PM


5:25 AM, 5/11/09, Update: Shuttle fueling begins

Working by remote control, engineers in firing room 4 at the Kennedy Space Center began fueling the shuttle Atlantis early Monday for launch on a long-awaited mission to service and upgrade the Hubble Space Telescope. LIftoff is targeted for 2:01:56 p.m.

The three-hour fueling procedure began at 4:41 a.m. when liquid hydrogen and liquid oxygen began flowing from storage tanks through lines to the shuttle's mobile launch platform and umbilicals in the twin tail service masts to either side of Atlantis' aft engine compartment.

If all goes well, a half-million gallons of supeprcold liquid oxygen and hydrogen rocket fuel will be pumped through the orbiter's main engine plumbing and into the external tank to set the stage for launch.

Flight controllers at the Johnson Space Center in Houston late Sunday updated Atlantis launch time by seven seconds to 2:01:56 p.m. With forecasters predicting a 90 percent chance of good weather in Florida, Atlantis' seven-member crew plans to head for the launch pad around 10:16 a.m. to strap in for launch.

Here are highlights for the remainder of today's countdown (in EDT):

EDT...........EVENT

04:41 AM......Liquid oxygen (LO2), liquid hydrogen (LH2) transfer line chilldown
04:51 AM......Main propulsion system chill down
04:51 AM......LH2 slow fill
05:19 AM......LO2 slow fill
05:26 AM......Hydrogen ECO sensors go wet
05:30 AM......Crew wakeup
05:31 AM......LO2 fast fill
05:41 AM......LH2 fast fill
06:56 AM......LH2 topping
07:41 AM......LH2 replenish
07:41 AM......LO2 replenish

07:41 AM......Begin 2-hour 30-minute built-in hold (T-minus 3 hours)
07:41 AM......Closeout crew to white room
07:56 AM......Astronaut support personnel comm checks
08:30 AM......NASA TV coverage begins
08:41 AM......Pre-ingress switch reconfig
09:36 AM......Final crew weather briefing
09:46 AM......Crew suit up begins
10:11 AM......Resume countdown (T-minus 3 hours)

10:16 AM......Crew departs O&C building
10:46 AM......Crew ingress
11:41 AM......Astronaut comm checks
12:01 PM......Hatch closure
12:36 PM......White room closeout

12:51 PM......Begin 10-minute built-in hold (T-minus 20m)
12:53 PM......NASA test director countdown briefing
01:01 PM......Resume countdown (T-minus 20m)

01:02 PM......Backup flight computer to OPS 1
01:06 PM......KSC area clear to launch

01:12 PM......Begin final built-in hold (T-minus 9m)
01:32 PM......NASA test director launch status verification
01:41:56 PM...Launch window opens
01:52:56 PM...Resume countdown (T-minus 9m)

01:54:26 PM...Orbiter access arm retraction
01:56:56 PM...Hydraulic power system (APU) start
01:57:01 PM...Terminate LO2 replenish
01:57:56 PM...Purge sequence 4 hydraulic test
01:57:56 PM...IMUs to inertial
01:58:01 PM...Aerosurface profile
01:58:26 PM...Main engine steering test
01:59:01 PM...LO2 tank pressurization
01:59:21 PM...Fuel cells to internal reactants
01:59:26 PM...Clear caution-and-warning memory
01:59:56 PM...Crew closes visors
01:59:59 PM...LH2 tank pressurization
02:01:06 PM...SRB joint heater deactivation
02:01:25 PM...Shuttle GPCs take control of countdown
02:01:35 PM...SRB steering test
02:01:49 PM...Main engine start (T-6.6 seconds)
02:01:56 PM...SRB ignition (LAUNCH)


02:45 PM, 5/10/09, Update: Weather improves to 90 percent 'go'

The shuttle Atlantis' countdown is proceeding smoothly toward launch Monday on an $887 million mission to service the Hubble Space Telescope, with forecasters now predicting a 90 percent chance of acceptable weather in Florida and only a slight chance of showers near an emergency runway in Spain.

On Saturday, the shuttle's fuel cell system was loaded with liquid oxygen and hydrogen to power the ship's electrical generators and early Sunday, the main engine avionics system was activated and checked out.

There are no technical problems of any significance at launch complex 39A and engineers are making preparations to retract a protective gantry late today, exposing Atlantis to view and setting the stage for fueling early Monday.

The three-hour fueling process is scheduled to begin around 4:51 a.m. If all goes well, commander Scott Altman, pilot Gregory C. Johnson, flight engineer and robot arm operator Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good  will head for the pad around 10 a.m. to strap in for launch at 2:01:49 p.m.

The primary goals of NASA's fifth and final mission to service and upgrade the Hubble Space Telescope are to install two new instruments - the Wide Field Camera 3 and the Cosmic Origins Spectrograph - six fresh batteries, six stabilizing gyroscopes, a replacement science data computer, a refurbished fine guidance sensor and insulation panels.

The astronauts also will attempt to repair two other instruments, the Advanced Camera for Surveys and the Space Telescope Imaging Spectrograph. Both failed in recent years and neither was designed to be serviced by spacewalking astronauts. While mission managers are optimistic the crew will be successful, there are no guarantees.

"There's not much margin for error," Hubble Program Manager Preston Burch said Sunday. "We'll need flawless execution from our astronaut team and we'll also need flawless performance from all of our hardware. But we have done extensive testing, extensive training and we're highly confident that we're going to have another successful mission like the ones we've had before."

Assuming an on-time launch Monday, McArthur, operating Atlantis' robot arm, will capture Hubble around 1 p.m. Wednesday. The first of five back-to-back spacewalks is scheduled to get underway at 8:16 a.m. Thursday.

"As John Kennedy said, we try these things not because they're easy but because they're difficult," said Project Scientist Dave Leckrone. "Particularly on this mission, we're going for broke. We set the bar extraordinarily high for ourselves. And nobody should consider this mission a failure ... if for some reason we don't get all things done to the hundred percent level. This is still an extraordinary  mission if we just get (the primary objectives) done."

NASA only has three days to get Atlantis off the ground this week or the flight will be delayed to May 22 because of a military operation on the Air Force Eastern Range that supports all East Coast launches and because of time needed to recharge new batteries bound for the Hubble Space Telescope.

The Florida forecast for Monday calls for near ideal conditions, but an approaching front could cause problems if Atlantis is delayed to Tuesday or Wednesday.

"We actually decreased the probability of KSC weather prohibiting launch (Monday) down to 10 percent," said shuttle weather officer Kathy Winters. "We have a 90 percent chance of good weather tomorrow for launch. Weather still is problematic if we happen to delay to the following day, Tuesday and Wednesday. It looks like we have a front that comes down into the area and that could cause some concerns if we happen to delay. We (have) a 40 percent chance of KSC weather prohibiting launch for Tuesday and also for Wednesday. So right now, day one does look good."

To reach the Hubble Space Telescope, Atlantis will be launched on an easterly trajectory that will carry it between 28.5 degrees north and south latitude. For launches to the International Space Station, NASA staffs three emergency runways in Europe - two in Spain and one in France - but only the southernmost, at Moron, Spain, is reachable by Atlantis.

Only one European landing site is required for a space station mission, but for Atlantis, the weather at Moron must be acceptable or the flight will be delayed.

"For Moron, our one overseas landing site, we do have just a slight chance of showers within 20 (nautical miles) due to a frontal system up to the north," Winters said. "Most of the activity should be up to the north, so just a slight concern there. So overall, pretty good weather at Moron."


06:00 PM, 5/9/09, Update: STS-125 Mission Preview Package

Editor's Note...

A 20,000-word preview package made up of three stories covering Hubble Servicing Mission No. 4, NASA's plans for a possible rescue flight and a history of the Hubble Space Telescope are available for download from CBS News:

The first take of the general mission preview is posted below (parts of this story originally were written for Astronomy Now magazine).

STS-125 Mission Preview:
High Hopes for a Final Hubble House Call

By WILLIAM HARWOOD
CBS News Space Consultant

NASA's fifth and final mission to service and upgrade the Hubble Space Telescope will add one of the most dramatic chapters yet to an ongoing saga that reads like "The Perils of Pauline." Or an over-the-top Hollywood screenplay about a scientific superstar repeatedly rescued from the brink of disaster.

"I don't think anybody except Arthur C. Clarke could have crafted such a great story," said astronomer-astronaut John Grunsfeld, the mission's lead spacewalker. "If it were just about Hubble, it would be a great story. But when you look about the science and the discoveries scientists have made using Hubble, then it just becomes an unbelievable story.

"I'm relatively glib in saying Hubble is perhaps the most important and productive scientific instrument ever created by humans. Only history will tell, but it's a truly remarkable story."

Grunsfeld, commander Scott Altman, pilot Gregory C. Johnson, robot arm operator Megan McArthur and fellow spacewalkers Michael Massimino, Andrew Feustel and Michael Good are scheduled for launch aboard shuttle Atlantis on May 11 at 2:01:49 p.m. It will be the second Hubble visit in a row for Altman and Massimino and the third for Grunsfeld. The rest are shuttle rookies.

Launch originally was scheduled for last Oct. 14, but just three weeks before takeoff a critical circuit in the telescope's science instrument data system malfunctioned. To restore full redundancy, NASA managers decided to delay the servicing mission to give engineers time to check out and certify a flight spare that had been used for ground testing. The replacement computer was delivered to the Kennedy Space Center on March 30, setting the stage for launch.

Hoping to extend Hubble's life well into the next decade, the four spacewalkers, working in two-man teams, plan five back-to-back excursions to install six new stabilizing gyroscopes, six new nickel-hydrogen battery packs, the replacement data computer and two new instruments, the $126 million Wide Field Camera 3 and the $81 million Cosmic Origins Spectrograph. Like all modern Hubble instruments, both are equipped with corrective optics to counteract the spherical aberration that prevents Hubble's 94.5-inch mirror from achieving a sharp focus.

The Atlantis astronauts also will attempt to repair two other instruments: the Space Telescope Imaging Spectrograph, which suffered a power supply failure in 2004, and the Advanced Camera for Surveys, which broke down in 2007. Neither instrument was designed to be serviced in orbit, but determined engineers devised custom tools and an ingenious plan for the spacewalkers to bypass the failed electronics.

The repair crew also plans to install an upgraded fine guidance sensor, new insulation and a grapple fixture that will permit attachment of a rocket motor or even NASA's new Orion manned spacecraft in the future to drive Hubble out of orbit when it is no longer able to do science.

"On Servicing Mission 4, we're going to give Hubble another extreme makeover," said Program Manager Preston Burch. "This makeover will be the best one yet because we will outfit Hubble with the most powerful and advanced imaging and spectrographic instruments available and we will extend Hubble's operating lifetime for five additional years."

Without Servicing Mission 4, engineers believe Hubble would be hard pressed to survive past 2010. But if the Atlantis astronauts are successful, they will leave behind an essentially new telescope, one that is equipped with a full suite of five operational scientific instruments for the first time since launch in 1990. And with new gyros and batteries, Hubble has a good chance of remaining fully operational long enough to work in concert with its eventual replacement, the James Webb Space Telescope.

"It's been seven years since we've serviced the Hubble space telescope," said Project Scientist David Leckrone. "And that interval of time, seven years, is twice as long as we should go in terms of servicing intervals. As a consequence of that, over the last few years we've seen significant deterioration within the set of scientific instruments that we provide to the astronomical community. The toolkit that the community uses to do all kinds of science has really diminished in its capabilities.

"I liken this to the situation of a champion athlete who is playing hurt, who has an injury and who is playing through the pain, still doing very well. But now, by golly, it's time to go off and get our surgery and get back to a hundred percent."

NASA has spent about $10 billion on the Hubble Space Telescope to date, making it one of the most expensive science projects in history. Asked whether it made sense to spend more money on a 20-year-old space telescope, former NASA Administrator Mike Griffin, the man who approved Hubble Servicing Mission 4 after it was canceled in the wake of the 2003 Columbia disaster, said it makes all the sense in the world.

"After we get done with it, it's not an old telescope," he told CBS News in a recent interview. "Every subsystem that needs refurbishment is being refurbished and it's getting a new complement of instruments. So the only part of it that's old is the optical metering structure and the glass. And the glass doesn't care. When they're done, it really is not an old telescope, it's a new telescope."

"So the question you want to ask yourself when you look at the value proposition, if for the cost of this shuttle flight - and bear in mind, most of the instrument costs and all that were already paid for - plus the team that we've been carrying, and it's about a $10-million-a-month team, if for whatever all that adds up to you could get yourself a new telescope in space, would you think that would be worthwhile? And I think most people, most astronomers, would say yes.

"Not because it's the biggest telescope, because we can build bigger ones on the ground. And with the new flexible mirror technology and multiple mirror technology, we can get some pretty large apertures," Griffin said. "But, being above the atmosphere still has value, and the best value of all is the coordination of ground-based observations and space-based observations. Between the two, you get a picture that is more than the sum of the parts.

"The question in brief is, if for what we're spending on this mission you could have a new telescope, would you buy one? And I think the answer is yes."

Bruce Margon, former associate director for science at the Space Telescope Science Institute in Baltimore, said shuttle servicing missions and NASA's ability to upgrade the telescope are the keys to the project's success.

"The thing to remember about these Hubble servicing missions is they're not just 'let's keep a groaning patient on life support,'" he said. "When you put new focal plane instruments into Hubble, you essentially leave with not only a brand new, but a much better observatory. And when you look at our graph of discoveries as reflected by published scientific papers versus year, it's an amazing thing because it just goes up every single year.

"The reason for that is not that the scientists who are using Hubble are smart. It's servicing. That's the reason, because when you leave Hubble you have not just something with better longevity but something that is an order of magnitude more capable than the previous thing, almost like it's a brand new generation of satellite. And the two new focal plane instruments for SM-4 are predicted to do the same thing. And it's not a whistling in the wind prediction."

For Ed Weiler, NASA's associate administrator for space science and a former Hubble project scientist, the key point is not the telescope's serviceability or even its obvious value to the astronomical community. It's the way Hubble has "brought the universe close up and personal to the average citizen."

"It's images have become part of our culture in our textbooks, magazines, art and even popular movies and TV programs," he said. "Although we probably never will be able to visit these places or objects, Hubble actually allows our human minds and spirits to travel light years and even billions of light years to the farthest reaches of the cosmos. And SM-4 will allow that dream to continue."

As for the telescope's astronomical price tag, Weiler agreed "you can build a lot of ground-based telescopes for that kind of money. But you can't get rid of the atmosphere."

"We've heard about adaptive optics (for ground-based telescopes) and how that's going to blow Hubble out of the water," he said. "We've heard that for 20 years now. We haven't seen it. What's amazing is, whenever a new telescope comes out on the ground, a press release will always come out that 'oh, this can see a hundred times better than Hubble, or 10 times better.' Yeah, it can, probably, over a very, very tiny field of view. But you don't see Eagle nebulas [right] on the cover of Time Magazine taken from the ground. It's taken from Hubble."

Launched from Atlantis in April 1990 with a famously flawed mirror, Hubble was equipped with corrective optics during a riveting, make-or-break 1993 shuttle repair mission. Since then, the Lockheed Martin-built observatory has generated a steady stream of discoveries, ranging from a more precise determination of the age of the universe - 13.7 billion years - to confirmation of the existence of super-massive black holes.

It has captured light from infant galaxies in the process of colliding and merging less than a billion years after the big bang birth of the universe. And it has helped refine our understanding of the life cycles of stars, from their birth in vast stellar nurseries to the supernova explosions and more common slow fading that mark old age and death.

In recent years, Hubble's remarkable vision has played a key role in the worldwide effort to understand the nature of dark energy, the enigmatic repulsive force that astronomers believe is accelerating the expansion of the universe.

Throughout it all, Hubble has beamed back a steady stream of spectacular photographs of planets, stars, nebulae and galaxies that have found their way into all facets of modern society, making the telescope an instantly recognized icon of science.

But keeping Hubble healthy in the unforgiving environment of space has not been easy. During a second servicing mission in February 1997, shuttle astronauts installed two new instruments - the Space Telescope Imaging Spectrograph and an infrared camera known as NICMOS - replaced a fine guidance sensor, a gyroscope assembly and installed a solid-state data recorder.

Because of multiple gyro failures in the late 1990s, Servicing Mission 3 was broken up into two shuttle flights, SM-3A in December 1999 and SM-3B in March 2002. During SM-3A, spacewalking astronauts installed a new flight computer, a second solid-state recorder, another fine guidance sensor and a full suite of six gyroscopes.

The objectives of SM-3B included installation of two new solar arrays, the Advanced Camera for Surveys, an experimental cooling system to revive Hubble's infrared camera and a replacement power control unit. The latter operation was analogous to a heart transplant, requiring the telescope to be shut down for the first time since launch.

One year after SM-3B, NASA was well into planning the fifth and final service call when the shuttle Columbia disintegrated during re-entry on February 1, 2003, the victim of heat shield damage caused by a piece of foam insulation falling from the ship's external fuel tank during launch.

A year later, in January 2004, then NASA Administrator Sean O'Keefe sent shock waves through the astronomical community when he abruptly canceled SM-4. The decision was announced two days after President Bush ordered NASA to complete the international space station and retire the shuttle by the end of 2010.

Citing safety concerns in the wake of Columbia and a lack of time and money to properly address them, O'Keefe said it was simply too dangerous to launch astronauts to the space telescope. Heat shield inspection and repair techniques were immature and NASA was still struggling to prevent foam insulation from falling off the shuttle's external tank.

More important, a Hubble crew could not seek "safe haven" aboard the international space station if some post-launch mishap or orbital debris impact prevented a safe re-entry. Hubble and the space station operate in different orbital planes and the shuttle does not carry enough rocket fuel to move from one to the other.

O'Keefe defended his hugely unpopular decision by citing the Columbia Accident Investigation Board, which recommended autonomous heat shield inspection and repair capability for any non-station shuttle flights. Under pressure from Hubble supporters in Congress, he agreed to let engineers explore options for a robotic servicing mission. But the scope of that mission was more limited, the technical risks were high and the projected cost was extreme.

Even so, project managers pressed ahead, fearing subsequent equipment failures in orbit that would knock the observatory out of action once and for all. And they had reason for concern.

In August 2004, the Space Telescope Imaging Spectrograph's one operational channel failed because of a power supply problem. The observatory's stabilizing gyroscopes were suffering problems and engineers worried the telescope's crucial battery packs, operating continuously since launch in 1990, were slowly degrading. No one knew when one might suddenly fail.

Against this backdrop of concern, NASA pressed ahead with space station assembly flights, implementing a series of upgrades to minimize foam shedding from external tanks. The agency also carried out a series of tests to perfect heat shield inspection and repair techniques.

In one critical test, spacewalking astronauts showed the shuttle's robot arm and a new 50-foot-long tile inspection boom were strong enough to support an astronaut if repairs were needed and the station was not available.

O'Keefe's replacement, Mike Griffin, made no secret of his desire to fly Servicing Mission 4, saying "Hubble servicing represents the highest priority utilization of a single shuttle mission that I can conceive."

Finally, after three successful post-Columbia missions and tests to demonstrate heat-shield repair tools and techniques, Griffin officially reinstated SM-4 in May 2006.

"I don't believe I've talked to anyone in the agency, from flight crew to flight ops managers to, you know, even budget guys, I don't believe I've talked to anyone who thinks we shouldn't do this," he said.

To address the safe haven concern, he ordered the shuttle program to process a second orbiter - Endeavour - in parallel and to have it ready for takeoff within a few days of an emergency being declared to carry out a rescue mission if needed (see "STS-400: Just in Case" for additional details).

"The way we've designed the mission, we've got an answer to each of the risk points that, I think, brings us right into the family of same risk level as going to the station," said Altman. "First, get rid of the debris at the source, fixing the tank. Number two is the ability to detect damage, we've got that. Three is the ability to repair, that's come along pretty well.

"And then the final thing is OK, if you screw all that up and you're stuck there with an unsafe vehicle to come home, what do you do? I think that was a big sticking point before with the administrator and now that we have this launch-on-need plan where another shuttle will come to us and rescue us, we have an answer for that, too."

As if to drive home the need for another servicing mission, the Advanced Camera for Surveys failed in January 2007, the apparent victim of a short circuit in its CCD control electronics. Its high resolution and heavily used wide field channels were knocked out of action, although its more limited solar blind channel continued to operate. That left Hubble with two fully operational instruments: The Wide Field Planetary Camera 2 and the Near Infrared Camera and Multi-Object Spectrometer, or NICMOS.

Then, after a software upgrade prior to the original October launch date for Atlantis, engineers were unable to restart the NICMOS cooling system, presumably because of ice particles that had formed in the coolant lines. Engineers are optimistic about ultimately melting the ice and restarting NICMOS, but as of this writing, the space telescope only has one fully operational instrument - WFPC-2 - and the solar blind channel of the Advanced Camera for Surveys.

"The WFPC-2 has proved to be very durable, but it's been there since December of '93," Burch said. "So it's close to 15 years old and really doesn't owe us anything. So we've got aging science instruments, we've got a weak complement of gyros. I think it's really tough to imagine going much beyond 2010 (without SM-4). And if we lost NICMOS and just became basically the WFPC-2 observatory in space, I think our operation would be cut back substantially. It costs a lot to operate this observatory, the operational cost per year is on the order of a hundred million dollars plus, which includes all the science grants and what not. And to only have the use of WFPC-2 with no prospects of a future servicing mission, I think NASA would feel strongly that they'd want to start putting the money toward the future rather than the past."

The rest of this story is available here: http://www.cbsnews.com/network/news/space/125/125_mission.html


12:20 PM, 5/9/09, Update: Weather in Spain improves slightly; countdown proceeding smoothly

The shuttle Atlantis' countdown continues to tick smoothly toward blastoff Monday with an 80 percent chance of good weather in Florida and improving conditions at an emergency runway in Spain, officials said Saturday.

"Our vehicle and our ground systems are really in great shape, we're really pleased about that, our launch preps are proceeding as we had planned and we really have no issues to report," NASA Test Director Jeff Spaulding told reporters during a morning countdown status briefing.

Shuttle weather officer Kathy Winters said the forecast for Florida has not changed, with meteorologists continuing to predict an 80 percent chance of acceptable conditions. But forecasters are still expecting a slight chance of showers near an emergency runway in Moron, Spain.

"It looks like our weather is going to be favorable for launch," Winters said of the Florida forecast. "Our primary concern at this point would be a chance for cumulus clouds developing with the sea breeze and also at Moron, we may have a slight chance for a shower there. It looks like most of the weather there would be up to the north, but there is a chance we could get some pre-frontal weather there, just a slight chance of an isolated shower in the area. So overall, the weather is favorable for launch day."

As with all shuttle launchings, NASA must have good weather at emergency runways in the United States and Europe in case of engine trouble or some other technical problem that might prevent a crew from reaching a safe orbit. Winters said high crosswinds are expected at Edwards Air Force Base,, Calif., on Monday, but conditions are acceptable at Northrup Strip in New Mexico.

The Florida forecast for Tuesday and Wednesday is 60 percent "go" with conditions improving throughout the week at Moron.

Because Atlantis, bound for the Hubble Space Telescope, is launching into a different orbit than flights to the International Space Station, only one of NASA's three European landing sites - Moron - is available.

As it turns out, the gap between the period when Atlantis could return to the Kennedy Space Center after an engine failure and the period when the crew could abort to a lower-than-planned orbit is only about 10 seconds long. But NASA flight rules require the availability of at least one European site before a launch can proceed.

The Spaceflight Meteorology Group at the Johnson Space Center in Houston monitors the weather at NASA's overseas runways and forecasters were more optimistic Saturday.

"SMG is not quite as concerned about it today as they were yesterday," Winters said. "It looks like that (frontal) boundary is going to be a little farther to the north so the weather's looking better in that location."

Working by remote control, engineers planned to load liquid hydrogen and oxygen aboard Atlantis this afternoon to power the shuttle's three electricity producing fuel cells. The procedure was expected to be complete by around 8 p.m., the start of a planned four-hour "hold" in the countdown.

If all goes well, the countdown will resume at midnight with main engine checkout, master events controller activation and a heat shield inspection. A protective gantry protecting the shuttle from the elements will be retracted Sunday afternoon to set the stage for fueling and blastoff Monday.


11:15 AM, 5/8/09, Update: Engineers set to start shuttle countdown; weather 80 percent 'go' for Monday launch but rain in Spain could cause problems (UPDATED at 5:45 p.m. with start of countdown, crew arrival)

Engineers late Friday started the shuttle Atlantis' countdown to blastoff Monday on a long-awaited fifth and final mission to service the Hubble Space Telescope. There are no technical problems of any significance at pad 39A and forecasters are predicting an 80 percent chance of good weather.

"All of our systems are in great shape," said NASA Test Director Jeremy Graeber. "We don't have any issues to report."

Engineers in Firing Room 4 at the Kennedy Space Center started the shuttle's countdown at 4 p.m., setting up a launch attempt at 2:01:49 p.m. Monday, 20 minutes after the opening of the Hubble launch window.

Atlantis commander Scott Altman, pilot Gregory C. Johnson, flight engineer Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good arrived at the spaceport around 5 p.m. to prepare for launch.

"Hello, Florida, it's great to be here at last!" Altman said on the runway after a flight from Houston. "It's been a long road to get here, we're all thrilled."

Originally scheduled for launch last October, the flight was put on hold when one of two channels in a critical data router aboard Hubble broke down three weeks before takeoff. Spare hardware was checked out, certified for flight and added to the crew's five-spacewalk mission, setting the stage for another launch try Monday.

"It's really cool for us to be here," Massimino said. "We've been training together for over two-and-a-half years. Our crew's gotten to know each other really well, we've become more like a family. For us to come down here and get a chance to get on the space shuttle in a couple of days and experience the dream of going into space and working on the Hubble together is something that we're really looking forward to."

Altman summed up the crew's feelings with an enthusiastic hand pump, saying "we are ready! Let's launch Atlantis!"

While the Florida forecast is favorable Monday, the weather in Spain could cause problems for NASA. Because of the trajectory Atlantis must fly to reach the space telescope, only one of NASA's three emergency runways in Europe is available in case of an engine failure or some other problem that might crop up during ascent.

At the designated trans-Atlantic landing site near Moron, Spain, forecasters are predicting a chance of showers within 20 nautical miles.

"There's a frontal boundary that's off to the west of the area there and pre-frontal weather tends to give you some showers," said shuttle weather officer Kathy Winters. "That is a concern for this launch. ... There is a decent chance of getting an isolated shower in the area."

NASA only has three days to get Atlantis off the pad or the flight will slip to May 22 because of an upcoming military operation on the U.S. Air Force Eastern Range that provides tracking and telemetry support for all rockets launched from Florida.

The forecast for Tuesday and Wednesday calls for a 60 percent chance of acceptable weather at the Kennedy Space Center, with conditions improving both days at Moron.


4:00 PM, 4/30/09, Update: NASA managers clear Atlantis for May 11 launch; first major shuttle retirement layoffs planned (UPDATED at 7:40 p.m. with NASA news conference)

With retirement of the space shuttle program expected next year after just nine more flights, NASA managers Thursday announced the first major round of job losses, saying 160 contractor workers would face layoffs Friday, the first of up to 900 jobs that will be lost between now and the end of the fiscal year.

"Tomorrow, we have a layoff of about 160 people on the team," shuttle Program Manager John Shannon told reporters. "Between tomorrow and the end of September, we will reduce the program by about 900 people. They are primarily manufacturing team members. We have delivered the last pieces of hardware that those team members produce and we don't keep them on the roles. And that is in order to get our budget down to the marks and the assumptions we made early on. So we will start tomorrow and continue with the workforce reduction we had outlined."

Several hundred jobs will be lost to attrition and some employees will transfer to other contractors or projects. The rest will be layoffs. Shannon would not say what companies will absorb the initial round of job reductions.

"Not all of the companies have notified their employees so I don't want to get real specific," he said. "But it's primarily for manufacturing and vendors."

Shuttle staffing peaked in the early 1990s, after delivery of the shuttle Endeavour and implementation of post-Challenger upgrades, when the contractor workforce climbed to around 24,000, with more than 4,000 NASA civil servants. The shuttle program currently employs about 1,600 NASA civil servants across the space agency and 13,800 contractors.

Production of major components such as external fuel tanks, built by Lockheed Martin, and solid-fuel boosters, built by ATK, is winding down as the program nears retirement.

As reported here earlier (see the April 13 status report), NASA's most recent authorization act included language that directed the space agency to take no action that "would preclude the continued safe and effective flight of the space shuttle after fiscal year 2010" if the next president - Barack Obama, as it turned out - decided to delay the orbiter's planned retirement. Depending on how one does the accounting, that directive had the potential to cost the agency nearly $90 million.

The Obama administration has expressed support for the addition of one shuttle flight to carry the Alpha Magnetic Spectrometer, an already-built, high-priority physics experiment, to the International Space Station.

But the Office of Management and Budget said the administration is sticking with the 2010 shuttle retirement date. The Bush administration's deadline was the end of fiscal 2010, or Sept. 30, 2010. The Obama administration has since told the space agency the deadline is the end of calendar 2010. Between now and then, NASA has nine shuttle flights planned, including the AMS mission. But only eight missions are currently funded. Money for the AMS flight has not yet been appropriated.

In any case, the "do not preclude" legislation expired Thursday.

"This is the first significant loss of manufacturing capability," Shannon said. "We are hitting that point where we have the last production activities going on. So it may have happened a little earlier (without the legislation), but only by a month or two."

The announcement came during a news conference after an executive-level flight readiness review that cleared the shuttle Atlantis for launch May 11 on NASA's fifth and final mission to service and upgrade the Hubble Space Telescope.

The mission is the only flight left on NASA's shuttle manifest that does not go to the International Space Station. Five back-to-back spacewalks, or EVAs, are planned to install two new instruments, six new batteries, a full set of six stabilizing gyroscopes, a replacement science instrument command and data handling system computer and a refurbished fine guidance sensor.

The astronauts also will attempt to repair two other science instruments, install new insulation and attach a grapple fixture that will make it easier for a future crew aboard a shuttle follow-on craft, or a robotic spacecraft, to drive the telescope out of orbit at the end of its lifetime.

With the upgrades and new instruments, mission managers hope Hubble will remain operational for an additional five years or more.

"We went over everything with the vehicle, with HST, with the space shuttle to make sure we're all ready to go fly," said Bill Gerstenmaier, chief of space operations at NASA headquarters. "We looked at everything extra hard. This is a different mission for us than we're used to. ... Every minute of this mission has got something that's important for the telescope or its important for shuttle operations. It's a real tribute to this team that they were able to pull all this together and give such an intricate timeline together."

At Hubble's high 350-mile altitude, the astronauts will be exposed to more risk of damage from space debris than a space station assembly crew and they won't be able to seek safe haven aboard the lab complex if any problem develops that might prevent a safe re-entry. The odds of a damaging impact from space debris average around 1-in-229 for the Hubble mission - a slight improvement over NASA's previous estimate - compared to around 1-in-330 for a typical space station assembly mission.

But the shuttle Endeavour, mounted atop pad 39B, has been processed in parallel and will be ready for launch on an emergency rescue mission if necessary. Given improved post-Columbia inspection techniques to detect heat shield problems, new repair materials and procedures and the availability of Endeavour if all else fails, NASA managers cleared Atlantis for launch.

"This is not your average shuttle flight, because we're going to Hubble and we're doing these five back-to-back EVAs," Shannon said. "Laid on top of this very ambitious mission is all of the inspection requirements that we laid in after Columbia. I'll tell you, the team has put together a plan that not only accomplishes all the major mission objectives for Hubble, but it also provides an equivalent inspection capability we would have on a typical ISS mission.

"We've got the ability to look at all the tile on the underside of the vehicle, we'll look at the reinforced carbon carbon nose, the wing leading edge, external tank doors. We also have the capability to do a focused inspection if required. And we're going to do an even better late inspection where we look for micrometeoroid-space debris damage on this flight because that's a bigger concern.  ... All of the flights we have flown since Columbia have provided the knowledge base for us to go into this flight very confidently. The team is absolutely there and we're really looking forward to launching on May 11."

On board will be commander Scott "Scooter" Altman, pilot Gregory C. Johnson, flight engineer and robot arm operator Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good. Altman, lead spacewalker Grunsfeld and Massimino are Hubble veterans while the rest are making their first flights.

Liftoff from pad 39A is planned for 2:01:49 p.m. on May 11, 20 minutes after the opening of the launch window to allow a more thorough analysis of possible space debris threats, or conjunctions. Assuming an on-time launch, McArthur, operating Atlantis' 50-foot-long robot arm, will grapple Hubble around 12:54 p.m. on May 13. The next day, starting at 8:16 a.m., Grunsfeld and Feustel will begin the first spacewalk to install the $126 million Wide Field Camera 3, the replacement science instrument computer and the new grapple fixture.

Massimino and Good will install the gyros and three of six batteries the next day. Grunsfeld and Feustel will venture back out again the following morning to install the $81 million Cosmic Origins Spectrograph and to attempt repairing the Advanced Camera for Surveys, which broke down in 2007.

Massimino and Good will try to fix the Space Telescope Imaging Spectrograph the day after that and install new insulation. Finally, Grunsfeld and Feustel will close out the Hubble servicing with a spacewalk to install the final three batteries, the replacement fine guidance sensor and additional insulation.

If all goes well, Hubble will be redeployed at 8:53 a.m. on May. 19 and Atlantis will return to Earth with a landing back at the Kennedy Space Center around 11:41 a.m. on May 22.


3:10 PM, 4/24/09, Update: Shuttle managers agree to retarget shuttle launch for May 11

Launch of the shuttle Atlantis on a mission to service and upgrade the Hubble Space Telescope was moved up one day and retargeted for May 11 after engineers and managers concluded Friday that processing could be accelerated without impacting required work. Senior managers will hold an executive-level flight readiness review next Thursday to discuss final clearance for launch.

By moving launch up one day, to 2:01:49 p.m. on May 11, NASA will get three attempts in a row to get Atlantis off the ground before standing down to make way for a military operation on the Air Force Eastern Range, the agency that provides telemetry and tracking support for all rockets launched from Florida.

If the weather or some other problem keeps Atlantis on the ground past May 13, launch will be delayed to May 22 at the earliest because of the range conflict and time needed to recharge the new batteries being delivered to Hubble aboard the shuttle.

A NASA spokesman said the only downside to moving launch up one day was a minor reduction in battery charging time, from 209 hours to 185. But that is still well above the 156-hour requirement for the new batteries and Hubble Program Manager Preston Burch agreed to the request to move launch up one day.

"Everybody signed off on it," said a NASA spokesman.

As reported earlier this week, NASA is hoping to get Atlantis off as soon as possible to avoid any problems for the next shuttle mission, a space station assembly flight by shuttle Endeavour. Endeavour currently is mounted atop launch pad 39B at the Kennedy Space Center, on stand by for launch on an emergency rescue mission if the Atlantis astronauts run into any problems that might prevent a safe re-entry.

Assuming a rescue flight is not needed, Endeavour will be moved to pad 39A and prepared for launch June 13 on the station assembly flight. But NASA will only have one week to get Endeavour off the ground. A so-called "beta angle cutout" will kick in June 21, preventing any shuttle visits to the station until after July 11 because of temperature constraints related to the angle between the sun and the plane of the space station's orbit.

Moving up the Atlantis launch date by one day would buy one more day of insurance to get the Hubble mission off ahead of the military range operation and at the same time, provide more cushion for the June mission. If the Atlantis flight slips behind the range operation, Endeavour's flight would face a delay to mid July.


9:45 AM, 4/24/09, Update: Engineers assess tool impact on shuttle payload bay door radiator (UPDATED at 11:20 a.m. with inspection results; no repairs needed)

A one-and-one-eighth-inch socket from a torque wrench fell from a service platform and hit the shuttle Atlantis' left payload bay door radiator during Hubble Space Telescope cargo installation earlier this week. In a lucky break for NASA, no one was injured, coolant lines in the radiator were not damaged and a dent where the socket impacted will not need repairs.

Atlantis is tentatively scheduled for liftoff May 12 on a fifth and final mission to service, repair and upgrade the Hubble Space Telescope. Shuttle managers planned to meet Friday for a second round of discussions on whether to move the launch date up one day.

NASA relies on tracking and telemetry equipment operated by the Air Force Eastern Range and a previously scheduled military operation will prevent any shuttle launches for about a week starting May 14. By moving launch up one day, to 2:01:49 p.m. on May 11, NASA could make three attempts in a row before standing down for the military operation.

The payload for the long-awaited mission - two new science instruments, new batteries, stabilizing gyroscopes and other critical equipment - was delivered to launch complex 39A Saturday and mounted in a payload changeout room in the pad's rotating service structure. After the RSS was moved into position around the orbiter's fuselage, the payload was installed in the shuttle's open cargo bay Wednesday.

The torque wrench socket fell from an upper-level access platform in the payload changeout room and hit Atlantis' left door's aft radiator panel about two inches from the inboard edge and five-and-a-half inches above the panel's bottom edge. Two workers experienced glancing blows, one on the arm and one on the back. A NASA spokeswoman said medical exams showed no injuries.

Embedded Freon coolant loops in the radiators carry away heat generated by the shuttle's electronics, but an inspection revealed the socket hit the face sheet over aluminum honeycomb material between two Freon lines and did not damage the cooling system.

Ultrasound inspections showed possible debonding between the face sheet and the underlying honeycomb where the socket impacted. But additional inspections showed the dented face sheet was not cracked and managers decided no repairs were necessary.


7:00 PM, 4/22/09, Update: NASA considers moving shuttle launch date up one day

NASA managers are debating whether to move up launch of the shuttle Atlantis one day, from May 12 to May 11, to get as many launch opportunities as possible before standing down to make way for a military operation that requires support from the Air Force Eastern Range starting May 14, officials said Wednesday.

The Eastern Range provides tracking and telemetry support for all rockets launched from Florida, as well as countdown dress rehearsals and other launch-related operations by NASA, the Department of Defense and commercial launch providers.

NASA is gearing up to launch the shuttle Atlantis on a fifth and final mission to service and upgrade the Hubble Space Telescope. The agency is aiming for a launch at 1:31 p.m. on May 12, but a military operation on the range, NASA sources say, will prevent any shuttle launch attempts for about a week starting May 14.

Hubble Space Telescope servicing mission payload is delivered to pad 39A
April 18 for installation aboard shuttle Atlantis (NASA photo)

As a result, NASA is looking into moving the shuttle launch date up one day, which would give the agency three opportunities in a row if needed.

Shuttle managers held a program-level flight readiness review Tuesday. Another meeting was held Wednesday to discuss launch date options and managers decided to meet again Friday for additional discussions. An executive-level FRR is scheduled for next week to review launch processing and to set an official launch date.

Sources say Atlantis can support a May 11 launch, but it's not yet clear if Hubble engineers can complete pre-launch tests in time to support an accelerated schedule.

NASA is hoping to get Atlantis off as soon as possible to avoid any problems for the next shuttle mission, a space station assembly flight by shuttle Endeavour. Endeavour currently is mounted atop launch pad 39B at the Kennedy Space Center, on stand by for launch on an emergency rescue mission if the Atlantis astronauts run into any problems that might prevent a safe re-entry.

Assuming a rescue flight is not needed, Endeavour will be moved to pad 39A and prepared for launch June 13 on the station assembly flight. But NASA will only have one week to get Endeavour off the ground. A so-called "beta angle cutout" will kick in June 21, preventing any shuttle visits to the station until after July 11 because of temperature constraints related to the angle between the sun and the plane of the space station's orbit.

Moving up the Atlantis launch date by one day would buy one more day of insurance to get the Hubble mission off ahead of the military range operation and at the same time, provide more cushion for the June mission. If the Atlantis flight slips behind the range operation, Endeavour's flight would face a delay to mid July.


11:25 AM, 4/17/09, Update: Shuttle Endeavour hauled to pad 39B for Hubble rescue duty (UPDATED at 3:30 p.m. with photo of Atlantis and Endeavour)

The space shuttle Endeavour was hauled to launch pad 39B at the Kennedy Space Center early Friday for work to prepare the ship for a flight NASA managers hope will never happen: a mission to rescue the astronauts charged with repairing and upgrading the Hubble Space Telescope.

Shuttle Endeavour atop pad 39B

The shuttle Atlantis is scheduled for launch May 12 from pad 39A on NASA's fifth and final mission to the space telescope. Because Hubble operates in a different orbit, the Atlantis astronauts would not be able to seek safe haven aboard the International Space Station if any problems develop that might prevent a safe re-entry.

As a result, NASA is processing Endeavour in parallel at nearby pad 39B for a quick-response launch on an emergency rescue mission if all else fails. Dana Hutcherson, the engineer in charge of Endeavour's ground processing, said the shuttle will be ready for launch seven days after Atlantis takes off if a major problem is spotted during initial heat shield inspections.

Endeavour's crawler-transporter slowly pulls away from
the shuttle's mobile launch platform

Assuming no non-repairable problems are found, Endeavour will be released from rescue stand by duty and engineers will focus on readying the ship for launch June 13 on a space station assembly mission. Endeavour will be moved to pad 39A for final processing and launch.

Pad 39B is being turned over to NASA's Ares 1 rocket program, which is gearing up for its first test flight later this summer or fall. The 330-foot-tall Ares 1 rocket, made up of a five-segment shuttle booster and a hydrogen-fueled upper stage, is being built to launch Orion crew capsules, the spacecraft that eventually will replace the shuttle.

Work to modify pad 39B for the Ares 1 system is well underway, with erection of new lightning towers and the removal of the familiar mast that used to be mounted atop the shuttle's service gantry. NASA is moving Endeavour to pad 39A for its June launch to clear the way for final Ares 1 pad modifications.

Space shuttle Atlantis on pad 39A Friday with
shuttle Endeavour in the background on 39B

Engineers plan to haul Atlantis' payload of Hubble science instruments, gyros, batteries and other equipment to pad 39A Saturday - "Family Day" at the Kennedy Space Center - for installation in the ship's cargo bay.

The protective gantries around both shuttles will be left open all day Saturday, giving space center workers, family members and friends a final chance to see two shuttles on their pads at the same time. Some 50,000 visitors are expected.


5:25 PM, 4/16/09, Update: Orbital debris risk for Hubble flight less severe than expected

Even factoring in a recent satellite collision, an analysis of the threat posed by space debris at the Hubble Space Telescope's 350-mile-high altitude shows the crew of shuttle Atlantis, scheduled for launch May 12 on a mission to service the observatory, will not face a dramatically higher risk of potentially catastrophic damage, a NASA official said today.

While the overall risk of impact damage is higher for a Hubble mission than a flight to the International Space Station, which orbits at a lower, less debris-filled altitude, the actual numbers are better than flight planners initially expected.

"It's not going to keep us on the ground," Steve Stich, manager of the orbiter project office at the Johnson Space Center, said in an interview. "Obviously, we know we're accepting a little higher risk for this flight. That's why we've tracked it very carefully."

Including the threat posed by debris from a satellite collision in February between a defunct Russian Cosmos satellite and an Iridium telephone relay station, the mean odds of a catastrophic impact during the Hubble mission are on the order of 1-in-221, which is below the 1-in-200 threshold that requires an executive-level decision by NASA's leadership.

A preliminary analysis put the odds at 1-in-185, but the numbers improved after recent radar observations and consideration of the shuttle's orientation in space during the Hubble mission. The planned orientation, or attitude timeline, reduces the crew's exposure to impacts that could damage critical areas of the ship's heat shield, the coolant loops in the shuttle's cargo bay door radiators and cockpit windows.

"The numbers changed recently from three factors," Stich said. "One, they went back and looked at the radar data and they took some more measurements and they found the debris environment isn't quite as severe. So that led to a reduction in the number.

"Two, we got an attitude timeline update that had higher fidelity breakdowns of the periods of time where we're going to be in attitudes to protect Hubble from the sun, and that was a factor in reducing that number. The third thing was, we actually were able to model HST in the payload bay and sometimes the HST actually provides a shield for the wing leading edge. Those three things combined took the risk from where we were last week, at 1-in-185, to 1-in-221 as of today."

For perspective, the overall odds of a catastrophic failure from all sources, including launch , orbital operations, re-entry and landing, are around 1-in-80.

Analysts took a conservative approach to the February satellite collisions, factoring in twice the amount of debris predicted by computer models. As it turns out, the amount of wreckage from the Iridium satellite was, in fact, roughly twice the predicted value. But radar tracking shows debris from the Cosmos matches the computer model's prediction. The overall risk was reduced accordingly.

Taking all that into account, the analysis shows a 1-in-141 chance of a potentially catastrophic problem from micrometeoroids/orbital debris - MMOD - if the crew simply flew the mission and made no attempt to inspect the shuttle for heat shield damage. The odds improve to 1-in-151 taking into account a planned inspection the day after launch, and to 1-in 243 with an inspection on the ninth day of the mission, after the Hubble Space Telescope is redeployed.

In those cases, the odds reflect the crew's post-Columbia ability to repair minor impact damage that might otherwise cause a catastrophic problem during entry. The mean value, 1-in-221, assumes a late inspection on flight day nine and an 86 percent chance of damage that could be successfully repaired.

"When you fold all that together, the residual risk of loss of crew and vehicle for the entire mission now is 1-in-221," Stich said. "That's MMOD, both the man-made and micrometeoroids, for the entire mission."

While an executive-level decision on what to do about the MMOD risk is not required in this case, shuttle program engineers will brief agency managers during a flight readiness review April 30 at the Kennedy Space Center.

"We've looked at Hubble very closely and we've done everything we can to mitigate the risks, the attitudes that we're flying, of course we've got our repair capability, we have launch on need (emergency rescue mission) ready and we've got late inspection," Stich said. "And for late inspection, for the hot (wing leading edge) panels, we've actually improved that inspection to get better resolution for panels 8 through 11 that actually drive the risk. So we've done everything we can to mitigate the risk."

MMOD risks for previous Hubble servicing missions covered a wide range of values, from 1-in-150 for a flight in 1993 to 1-in-761 for a mission in 1999. For the most recent mission in 2002, the MMOD risk was 1-in-365. Those numbers don't take into account post-Columbia inspection and repair techniques, not to mention the agency's plan to have a second shuttle ready for launch on an emergency rescue mission if necessary.

"The bottom line is, since return to flight this one is in the ball park" with past Hubble missions, an official said.

The Hubble servicing mission originally was planned for last October, but the flight was delayed to May when a data processing system on the telescope broke down. Going into that launch campaign, shuttle Program Manager John Shannon told reporters NASA planned to do everything possible to reduce exposure to MMOD damage.

"Because we recognize it as a significant risk, we have already taken all the actions we can as far as attitude timeline in putting the vehicle in a position where if we get micrometeoroid or orbital debris pieces coming at the vehicle, the come typically along the velocity vector," Shannon said.

"So you'll see with our attitude that we'll typically put the shuttle main engines toward the velocity vector (in the direction of travel). It protects the windows and the payload bay and the Freon loops and the RCC (nose cap and wing leading edge panels). So they have optimized the attitude timeline as much as they can for this mission. And we'll do our inspections, so we will know by the end of the mission if anything is required to go repair or not."

To put the MMOD numbers in perspective, the MMOD risk for the most recent space station assembly flight was 1-in-332. The two flights before that came in at 1-in-333 and 1-in-339 respectively.

"The 1-in-200 is a fairly arbitrary number that was decided upon kind of by consensus to make sure we have the discussion and that the discussion takes place at the right level," Shannon said. "When you get to a risk greater than 1-in-200, it was decided that decision should be made at the agency level."

Based on the latest analysis, that will not be necessary for Atlantis' upcoming flight. But the analysis highlights the increased risk the Atlantis astronauts will face because of the unique nature of their mission.

Unlike missions to the International Space Station, the Atlantis astronauts cannot seek safe haven aboard the lab complex if some sort of major problem develops that might prevent a safe re-entry. The telescope and the space station are in different orbits and Atlantis cannot change its trajectory enough to reach the lab complex.

As a result, the shuttle Endeavour will be moved to pad 39B Friday for work to ready the ship for a quick-response launch on an emergency rescue mission if necessary. The rescue mission would be known as STS-400.

But the Atlantis crew will only have enough supplies to last about 25 days on their own, even with extreme power downs. That means a rescue mission would need to approved relatively early in the Atlantis mission. If a problem is discovered during the late inspection toward the end of the mission, it's not clear Endeavour could be launched in time to pull off a rescue.

As a result, Shannon said, "we worked very hard to develop repair capabilities for micrometeoroid/orbital debris damage, we've got plugs we can put in the reinforced carbon carbon (wing leading edge panels), we've got the non-oxide adhesive we can put over any cracks or any kind of holes. I think 400 is there more for an ascent debris kind of situation, some kind of a really gross ascent problem like we had on Columbia. 400 would be very effective for that kind of case.

"For the MMOD case where we saw something during late inspection, if it were a case where we did not think we had repair capability for it, it's questionable whether 400 could get off the pad in time to go do any kind of a rescue. ... I think our protection for MMOD lies in our repair capability. We've spent a lot of time doing hypervelocity impacts on RCC materials, doing our repairs and putting them in the arc jet facility and we've had outstanding results. So we feel very comfortable about what we have.

"It would take a very rare, and very significant, large-size damage from MMOD in a critical area to cause us to have to consider 400 for that kind of case."


5:55 PM, 4/13/09, Update: NASA plans to stop work protecting option for shuttle extension past 2010 deadline; will focus on nine flights between now and end of calendar 2010

Facing a tight budget, a 2010 deadline to end space shuttle operations and a lack of concrete political support to fund additional flights or stretch out the current manifest, NASA managers are meeting this week to discuss the impact of ending efforts that have been keeping open the possibility of extending the shuttle program past the current deadline.

In a note to shuttle managers and engineers last week that was obtained by CBS News, shuttle Program Manager John Shannon outlined the issues in stark terms, reflecting the lack of any political action to fund shuttle flights past the end of 2010.

"You have heard me say that 'hope is not an effective management tool' on many occasions," he wrote. "It is my position that we cannot continue to spend money to retain the capability to fly additional space shuttle missions, hoping that someone will recognize the national assets we are giving up.

"We have to take our destiny in our own hands and manage within the limited budget we have been given and ensure that we will fly the full manifest and leave the International Space Station in the best configuration possible."

NASA's most recent authorization act included language that directed the space agency to take no action that "would preclude the continued safe and effective flight of the space shuttle after fiscal year 2010" if the next president - Barack Obama, as it turned out - decided to delay the orbiter's planned retirement. Depending on how one does the accounting, that directive had the potential to cost the agency nearly $90 million.

The Obama administration has expressed support for the addition of one shuttle flight to carry the Alpha Magnetic Spectrometer, an already-built, high-priority physics experiment, to the International Space Station.

But the Office of Management and Budget said the administration is sticking with the 2010 shuttle retirement date. The Bush administration's deadline was the end of fiscal 2010, or Sept. 30, 2010. The Obama administration has since told the space agency the deadline is the end of calendar 2010. Between now and then, NASA has nine shuttle flights planned, including the AMS mission. But only eight missions are currently funded. Money for the AMS flight has not yet been appropriated.

"If we're going to make this thing work, we've got to focus 100 percent on those nine flights and make sure we get them done," said a senior NASA manager who spoke on background and asked not to be identified. "We can no longer continue to split our attention both ways. We're going to have to have a hard discussion with our folks ... we're going to have to make those nine flights real. And that's what we're going to go do."

The Obama administration has offered little visible guidance beyond support for the AMS flight and the shuttle deadline clarification. The president has yet to name a replacement for former NASA Administrator Mike Griffin, the Bush-administration appointee whose tenure ended with Obama's inauguration.

Griffin inherited the job of overseeing the post-Columbia decision to complete the space station and retire the shuttle by the end of 2010 and to develop a new spacecraft to replace the shuttle. That vehicle, the Apollo-like Orion capsule and its Ares 1 rocket, is intended to ferry astronauts to and from the space station and, eventually, on to the moon.

But the Orion/Ares system will not be ready for use until 2015. During the five-year gap between the shuttle's retirement and the debut of the new rocket, NASA and it's international partners will have to hitch rides to the space station aboard Russian Soyuz spacecraft.

Concern about reliance on the Russians has prompted several key lawmakers to lobby for additional funding to extend shuttle operations, stretching out the current manifest to close or narrow the gap. Rep. Bill Posey (R-FL), whose district includes the Kennedy Space Center, and Rep. Debbie Wasserman Schultz (D-FL) introduced legislation earlier this month to extend shuttle operations beyond 2010 and to accelerate development of the Ares/Orion spacecraft.

But so far, no such funding has been approved or even money to cover the costs of simply keeping the extension option open.

Complicating the picture for NASA planners, there is a very real possibility that one or two of the final shuttle missions currently envisioned will slip into the October-December 2010 timeframe, i.e., the first quarter of fiscal 2011. There is no money in NASA's projected 2011 budget for any shuttle operations beyond $300 million or so intended for retirement activities.

As a result, NASA now plans to terminate work that kept open the option of a shuttle extension when the current legislation expires at the end of the month.

"We don't have enough money to keep carrying various options to extend and add additional flights," said the NASA manager who spoke on condition of anonymity. "We don't have funding right now for that first quarter of 2011. So we've got to save money out of '10 to roll into that first quarter of fiscal year 2011.

"So that's what John's kind of saying in his note to the troops, that we can no longer carry options, we've got to make some hard decisions if we want to try to get these nine remaining flights flown. Where we were kind of slowing things down and we were buying some extra spare parts and kept some subs (subcontractors) around and stuff, it's now time we've got to start making those hard decisions to really start trying to save money so we ... can support all the way to the end of calendar year 2010."

Shuttle program managers were scheduled to meet Tuesday and Wednesday at the Kennedy Space Center for a quarterly budget review. The final missions on NASA's shuttle manifest are critical flights to deliver spare parts and supplies to the International Space Station and NASA managers don't want to risk losing one because money that could have helped cope with technical problems or launch delays had been diverted to building hardware for flights that are not expected to be approved.

"It's not cut and dried," said the NASA manager. "Even though we're going to start ramping back down again, we still haven't really lost capability. I've still got this hardware sitting around and if someone has some great idea this summer that we want to go do this and they give us a ton of money, we could probably figure out a way to get the thing flying again. But we can't protect for that option."

In his email last week, Shannon said "here is our dilemma: Do we keep up the 'do not preclude' strategy, spending at a level that is inconsistent with our current budget line, in the hopes that someone will come along with additional funding to allow us to fly the full manifest? Or do we make the difficult decisions to cut core future capability in order to fly the current manifest within our current budget marks?"

After stating his position that NASA must protect the existing manifest in the absence of any concrete political support and funding for extending shuttle operations, he said "unfortunately, it will be extraordinarily painful to let go of the team members that have ensured our success for 28 years - the testing teams, the manufacturing teams, the teams that integrate, ship and assemble the most complex and capable rocket in history.

"I ask that you put aside the emotions, and concentrate on what is known," Shannon concluded. "We have a limited budget and a clear mission - fly through STS-134 (the final shuttle mission) safely and successfully."


11:35 AM, 4/10/09, Update: Shuttle Endeavour, Hubble rescue shuttle, moved to VAB

The space shuttle Endeavour, the designated rescue ship for next month's Hubble Space Telescope servicing mission, was hauled from its processing hangar to the Vehicle Assembly Building at the Kennedy Space Center early Friday for attachment to an external tank and solid-fuel boosters. Rollout to pad 39B is planned for April 17.

Shuttle Endeavour is moved into the Vehicle Assembly Building
(Credit: Justin Ray/Spaceflightnow.com)

The shuttle Atlantis already is mounted atop pad 39A for work to ready the ship for blastoff May 12 on a fifth and final mission to service and upgrade the space telescope. It is the only flight left on NASA's shuttle manifest that is not bound for the International Space Station.

Because the Hubble Space Telescope and the space station are in different orbits, the Atlantis crew cannot seek safe haven aboard the lab complex if the shuttle experiences any sort of problem that might prevent a safe re-entry. As a result, NASA is processing Endeavour in parallel for a quick-response launch from pad 39B if a rescue mission is required.


3:00 PM, 3/31/09, Update: Shuttle Atlantis hauled to launch pad

The space shuttle Atlantis, bolted to a mobile launch platform atop an Apollo-era crawler-transporter, was hauled to launch pad 39A at the Kennedy Space Center Tuesday for work to ready the ship for blastoff May 12 on a fifth and final mission to service the Hubble Space Telescope.

Originally scheduled for launch last Oct. 14, the long-awaited Hubble overhaul was delayed when one channel of a critical data processing system unit aboard the telescope failed just two weeks before liftoff. NASA managers decided to replace Hubble's entire science instrument command and data handling unit, or SI/C&DH, to restore redundancy and improve reliability.

But testing a spare ground unit at the Goddard Space Flight Center in Greenbelt, Md., getting it certified for flight, and working the mission back into NASA's shuttle manifest ended up delaying Atlantis and Hubble Servicing Mission 4 - SM-4 - for seven months.

The replacement SI/C&DH was delivered to the Kennedy Space Center Monday and Atlantis, attached to an external fuel tank and two solid-fuel boosters, took its first step toward space with a six-and-a-half-hour, 3.2-mile trip from the Vehicle Assembly Building to pad 39A Tuesday.

Space shuttle Atlantis is moved to pad 39A for May 12 launch
(Credit: William Harwood)

Shuttle commander Scott Altman, pilot Gregory C. Johnson, flight engineer Megan McArthur, and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel, and Michael Good plan to fly to Kennedy late this week to inspect the replacement computer unit before it is moved to the pad April 18, along with the rest of the Hubble payload, for installation in Atlantis' cargo bay.

Hubble SM-4 is the fifth and final planned shuttle mission to the space telescope (SM-3 was spread across two flights). During five back-to-back spacewalks, the Atlantis astronauts plan to install a new camera, called the Wide Field Camera 3, the Cosmic Origins Spectrograph, a full set of batteries, six new stabilizing gyroscopes, a new fine guidance sensor, new insulation, and to carry out repairs on two other science instruments that are currently out of action.

The new 135-pound science instrument command and data handling unit will be wired into Hubble's electrical system during the first spacewalk, after the Wide Field Camera 3 is installed.

As it now stands, no major mission objectives have been deleted despite the late addition of the SI/C&DH installation. But to get everything done, the astronauts must be able to complete a complex repair of the Advanced Camera for Surveys during a single spacewalk. The original flight plan broke that task into two parts.

If it turns out the astronauts need more time for the repair work, the fine guidance sensor replacement could be deleted.

There are no technical problems of any significance with Atlantis or its payload, but analysts are still evaluating the threat posed by orbital debris at Hubble's 350-mile-high altitude. Because of a satellite collision in February, the debris environment is somewhat worse at Hubble's altitude and as of this writing the mean chance of a catastrophic impact during the shuttle visit is believed to be around 1-in-185.

Odds worse than 1-in-200 require an executive-level decision on whether the additional risk is acceptable. Engineers say additional analysis, possible changes to the shuttle's orientation in space and other factors are expected to improve those odds and senior managers appear confident Atlantis ultimately will be cleared for flight.

Shuttle program managers plan to meet April 20 and 21 to review launch processing, followed by an executive-level flight readiness review April 30 at the Kennedy Space Center to formally clear the ship for launch. If no problems develop, Atlantis' countdown will begin May 9 for a launch attempt the afternoon of May 12.

The last published launch time was 1:21 p.m. EDT, about 20 minutes into the Hubble launch window. But flight planners may adjust that pending additional analysis of payload weight and ascent performance margin.

Here is a brief overview of the crew's flight plan (assumes a launch at 1:21 p.m. on May 12; spacewalks, or EVAs, would begin around 6:46 a.m. each day):

Because the Hubble Space Telescope is in a different orbit than the international space station, the Atlantis astronauts cannot seek safe haven aboard the lab complex if a major problem develops that might prevent a safe re-entry.

As a result, NASA plans to move the shuttle Endeavour to launch pad 39B on April 17 to ready the ship for a quick-response blastoff on an emergency rescue mission if needed. If not, Endeavour will be moved to pad 39A after Atlantis lands for normal processing and launch around June 13 on the next space station assembly mission.


09:00 PM, 10/30/08: Endeavour cleared for 11/14 launch; Hubble mission delayed to at least May

NASA managers today cleared the shuttle Endeavour for launch Nov. 14 on a space station assembly and servicing mission. But work to test a component needed by the Hubble Space Telescope will not be finished in time for launch aboard the shuttle Atlantis in February. That flight, Hubble Servicing Mission 4, originally was scheduled for launch Oct. 14 but it was delayed when a critical science data relay unit aboard the observatory failed in late September. NASA managers decided to delay the Hubble flight to mid February to give engineers time to test replacement electronic gear, but detailed checkout and problems with the equipment require additional troubleshooting, delaying the long-awaited flight to May at the earliest.

"Today, after a thorough review at the Goddard Space Flight Center of the work to go preparing the spare science instrument command and data handling system, the science mission directorate has informed the space operations mission directorate and the space shuttle program that the spare unit will not be available to support a February launch date with acceptable schedule margin and technical risk," Jon Morse, director of astrophysics at NASA headquarters, told reporters.

Engineers now plan to remove Atlantis from its external tank and solid-fuel boosters and give that "stack" to the shuttle Discovery for launch Feb. 12 on a flight to deliver a final set of solar arrays to the international space station. If all goes well, the Hubble mission could take off around May 12, two weeks before launch of a Russian Soyuz spacecraft May 25 that would carry three crew members to the space station, boosting the lab's crew size to six.

But that schedule assumes engineers at Goddard can resolve anomalies in the replacement Hubble command and data handling subsystem and complete an exhaustive series of tests to verify its flight readiness. Preston Burch, Hubble program manager at Goddard, said he's confident the hardware will be ready to fly in May.

"I'm very confident, personally, that we can troubleshoot the anomaly that we're currently working on and get it ready to fly," Burch said. "We have all the design documentation, all the schematics and everything, we have a very smart group of engineers and technicians that are working on this. This is a glitch on a black box that's well known, well understood, flight proven, so I don't see this as a huge, insurmountable deal. It's not like we're doing something experimental in quantum physics or anything like that. So I suspect we're going to have success with this."

The Hubble trouble began Sept. 27 when the telescope's control unit and science data formatter, or CU/SDF-A, suffered a "hard" failure, preventing ground controllers from receiving data from the science instruments. The A and B channels of the redundant science instrument data handing system are located on the same electronics tray and NASA managers decided to replace the entire unit with a flight spare to restore lost redundancy.

But the flight spare must be tested and recertified, forcing NASA to delay Atlantis' launch from mid October to mid February. In the meantime, after initial problems, engineers successfully activated the B-side electronics aboard Hubble and resumed science operations.

But they have not been so fortunate with the spare hardware on the ground. During initial checks, engineers were able to activate the spare unit's B-side but they had problems with its counterpart. Those problems prompted speculation and reports of potentially serious trouble.

"There's been a lot of speculation in the media and I guess they've been going to sources that don't have any direct knowledge of the condition of the hardware," Burch said. "That's really unfortunate."

He said the spare science instrument command and data handling system "was delivered to NASA in the early 90s and at that time, the acceptance test program had not been completed."

"There was some open paperwork and there were some anomalies that had not been resolved at that time," Burch said. "In the early 90s, we were focused on preparations for the first servicing mission and so did not want to spend the resources and the time on the SIC&DH spare at that time. So we set it aside with the understanding that we would be able to address any of the open issues associated with it and get it in a flight worthy condition in the future should it be needed. And now that time is here. So it's been quite a few years since we've looked at this particular unit."

Along with the spare SIC&DH, Goddard also has an engineering unit used for testing. Here's how Burch explained the issue:

"We have an engineering model SIC&DH that's a single string unit, it doesn't have two sides, an A and a B, but it's built just like the flight unit," Burch said. "But it hasn't gone through the same type of program that the flight unit has gone through and so it's not considered to be a flight unit. But we have had a need over the past 15 years to occasionally use an SIC&DH on the ground for testing instruments and for testing the NICMOS (infrared camera) cooling system that you'll recall we developed in preparation for servicing mission 3B, which we launched in March 2002.

"As a result of that, we availed ourselves of the spare unit and we took some equipment off of it. We removed the B side CU/SDF, the control unit/science data formatter, because we needed one to use on the engineering model SIC&DH. We took off one of the computer processors and put that on and one of the (data interface units). So there was some disassembly of that unit, but it's otherwise in a pristine condition. So when we found ourselves with a need to fly it, we immediately went back and rounded up the (needed hardware). And now we are operating it on the ground.

"We tried to fire up the A side CU/SDF Friday and it didn't handle the commands properly that were being sent to it to turn it on," Burch said. "So after a little bit of trying that, we thought well, we might have a problem with our test configuration. So we thought, why not try the B side and see how that works? So we switched over to the B side and that came up and worked just fine. We tested the B side for a few days and then decided to go back to the A side to try to troubleshoot that.

"Initially the unit did not respond properly but with repeated attempts at commanding the A side, the A side slowly came around and started handling the commands properly. At one point, it was performing as well as the B side, it was handling multiple format-type commands, it was handling data from multiple science instruments ... it was behaving beautifully. Then it stopped behaving like it should and we restarted it. And so it's been kind of a back and forth deal with it.

"What we're trying to do now is to understand what the sensitivity of that unit is to things like temperature. There are a number of suspicions about what could be the cause of the problem. What we suspect is, there's a workmanship or a parts problem on that unit, which is causing this glitch and we're going to need to try to troubleshoot that."

Burch said he was confident engineers will track down the problem, fix it and press ahead with testing.

"Our plan overall takes something on the order of about six-and-a-half months from now," he said. "There's about a month or so devoted to inspecting and resolving any of the performance issues associated with it, about three months for environmental tests and then about two to two-and-a-half months to do final testing and shipping down to Kennedy Space Center."

The primary goals of Hubble Servicing Mission 4 are to install new batteries and stabilizing gyros, two new science instruments, a replacement fine guidance sensor and new insulation. The astronauts also plan to repair two of Hubble's instruments, the Advanced Camera for Surveys and the Space Telescope Imagine Spectrograph.

Three of Hubble current set of six gyroscopes have failed, its six nickel-hydrogen batteries are nearly 20 years old and only hold half the charge they were designed for and its data subsystem no longer has redundancy. Even so, Burch said the observatory should be able to ride out the latest servicing mission delay with no major problems.

"Right now, we are doing science on two gyros and we have one gyro remaining that's a spare that is off," he said. "We should be able to easily go another year with the current gyros we have."

Hubble's batteries currently are operating at half their rated capacity. While that is sufficient for normal operations, engineers have no idea how long they will last.

"Nobody has ever operated nickel-hydrogen batters in orbit as long as Hubble has," Burch said. "The way we use the batteries, we've been able to get smarter and come up with a better regimen for operating them on a daily basis. But that still doesn't get around the fact that they're well past their design lifetime. The prudent thing to do is replace them. But I think we'll be fine with batteries for the next several months."

As for the no-longer-redundant science data handling subsystem aboard Hubble, "I am very confident the B side will continue to operate normally," Burch said.


5:30 PM, 12/4/08: Hubble servicing mission officially retargeted for May 12

NASA managers today officially re-targeted shuttle mission STS-125 - the final planned flight to service and upgrade the Hubble Space Telescope - for launch May 12, 2009. The long-awaited mission originally was planned for October, but the flight was put on hold after an electronic component aboard the observatory failed Sept. 27. Instead, NASA pressed ahead with the just-complete STS-126 space station assembly mission.

Hubble managers initially held out hope for a launch in February, after tests and checkout of spare computer gear to replace the system that failed in orbit. But that schedule proved to be too optimistic and NASA managers decided to proceed with the next station assembly flight Feb. 12.

Engineers now believe the Hubble computer gear will be ready in time for a launch attempt May 12.


09:00 PM, 10/30/08: Endeavour cleared for 11/14 launch; Hubble mission delayed to at least May

NASA managers today cleared the shuttle Endeavour for launch Nov. 14 on a space station assembly and servicing mission. But work to test a component needed by the Hubble Space Telescope will not be finished in time for launch aboard the shuttle Atlantis in February. That flight, Hubble Servicing Mission 4, originally was scheduled for launch Oct. 14 but it was delayed when a critical science data relay unit aboard the observatory failed in late September. NASA managers decided to delay the Hubble flight to mid February to give engineers time to test replacement electronic gear, but detailed checkout and problems with the equipment require additional troubleshooting, delaying the long-awaited flight to May at the earliest.

"Today, after a thorough review at the Goddard Space Flight Center of the work to go preparing the spare science instrument command and data handling system, the science mission directorate has informed the space operations mission directorate and the space shuttle program that the spare unit will not be available to support a February launch date with acceptable schedule margin and technical risk," Jon Morse, director of astrophysics at NASA headquarters, told reporters.

Engineers now plan to remove Atlantis from its external tank and solid-fuel boosters and give that "stack" to the shuttle Discovery for launch Feb. 12 on a flight to deliver a final set of solar arrays to the international space station. If all goes well, the Hubble mission could take off around May 12, two weeks before launch of a Russian Soyuz spacecraft May 25 that would carry three crew members to the space station, boosting the lab's crew size to six.

But that schedule assumes engineers at Goddard can resolve anomalies in the replacement Hubble command and data handling subsystem and complete an exhaustive series of tests to verify its flight readiness. Preston Burch, Hubble program manager at Goddard, said he's confident the hardware will be ready to fly in May.

"I'm very confident, personally, that we can troubleshoot the anomaly that we're currently working on and get it ready to fly," Burch said. "We have all the design documentation, all the schematics and everything, we have a very smart group of engineers and technicians that are working on this. This is a glitch on a black box that's well known, well understood, flight proven, so I don't see this as a huge, insurmountable deal. It's not like we're doing something experimental in quantum physics or anything like that. So I suspect we're going to have success with this."

The Hubble trouble began Sept. 27 when the telescope's control unit and science data formatter, or CU/SDF-A, suffered a "hard" failure, preventing ground controllers from receiving data from the science instruments. The A and B channels of the redundant science instrument data handing system are located on the same electronics tray and NASA managers decided to replace the entire unit with a flight spare to restore lost redundancy.

But the flight spare must be tested and recertified, forcing NASA to delay Atlantis' launch from mid October to mid February. In the meantime, after initial problems, engineers successfully activated the B-side electronics aboard Hubble and resumed science operations.

But they have not been so fortunate with the spare hardware on the ground. During initial checks, engineers were able to activate the spare unit's B-side but they had problems with its counterpart. Those problems prompted speculation and reports of potentially serious trouble.

"There's been a lot of speculation in the media and I guess they've been going to sources that don't have any direct knowledge of the condition of the hardware," Burch said. "That's really unfortunate."

He said the spare science instrument command and data handling system "was delivered to NASA in the early 90s and at that time, the acceptance test program had not been completed."

"There was some open paperwork and there were some anomalies that had not been resolved at that time," Burch said. "In the early 90s, we were focused on preparations for the first servicing mission and so did not want to spend the resources and the time on the SIC&DH spare at that time. So we set it aside with the understanding that we would be able to address any of the open issues associated with it and get it in a flight worthy condition in the future should it be needed. And now that time is here. So it's been quite a few years since we've looked at this particular unit."

Along with the spare SIC&DH, Goddard also has an engineering unit used for testing. Here's how Burch explained the issue:

"We have an engineering model SIC&DH that's a single string unit, it doesn't have two sides, an A and a B, but it's built just like the flight unit," Burch said. "But it hasn't gone through the same type of program that the flight unit has gone through and so it's not considered to be a flight unit. But we have had a need over the past 15 years to occasionally use an SIC&DH on the ground for testing instruments and for testing the NICMOS (infrared camera) cooling system that you'll recall we developed in preparation for servicing mission 3B, which we launched in March 2002.

"As a result of that, we availed ourselves of the spare unit and we took some equipment off of it. We removed the B side CU/SDF, the control unit/science data formatter, because we needed one to use on the engineering model SIC&DH. We took off one of the computer processors and put that on and one of the (data interface units). So there was some disassembly of that unit, but it's otherwise in a pristine condition. So when we found ourselves with a need to fly it, we immediately went back and rounded up the (needed hardware). And now we are operating it on the ground.

"We tried to fire up the A side CU/SDF Friday and it didn't handle the commands properly that were being sent to it to turn it on," Burch said. "So after a little bit of trying that, we thought well, we might have a problem with our test configuration. So we thought, why not try the B side and see how that works? So we switched over to the B side and that came up and worked just fine. We tested the B side for a few days and then decided to go back to the A side to try to troubleshoot that.

"Initially the unit did not respond properly but with repeated attempts at commanding the A side, the A side slowly came around and started handling the commands properly. At one point, it was performing as well as the B side, it was handling multiple format-type commands, it was handling data from multiple science instruments ... it was behaving beautifully. Then it stopped behaving like it should and we restarted it. And so it's been kind of a back and forth deal with it.

"What we're trying to do now is to understand what the sensitivity of that unit is to things like temperature. There are a number of suspicions about what could be the cause of the problem. What we suspect is, there's a workmanship or a parts problem on that unit, which is causing this glitch and we're going to need to try to troubleshoot that."

Burch said he was confident engineers will track down the problem, fix it and press ahead with testing.

"Our plan overall takes something on the order of about six-and-a-half months from now," he said. "There's about a month or so devoted to inspecting and resolving any of the performance issues associated with it, about three months for environmental tests and then about two to two-and-a-half months to do final testing and shipping down to Kennedy Space Center."

The primary goals of Hubble Servicing Mission 4 are to install new batteries and stabilizing gyros, two new science instruments, a replacement fine guidance sensor and new insulation. The astronauts also plan to repair two of Hubble's instruments, the Advanced Camera for Surveys and the Space Telescope Imagine Spectrograph.

Three of Hubble current set of six gyroscopes have failed, its six nickel-hydrogen batteries are nearly 20 years old and only hold half the charge they were designed for and its data subsystem no longer has redundancy. Even so, Burch said the observatory should be able to ride out the latest servicing mission delay with no major problems.

"Right now, we are doing science on two gyros and we have one gyro remaining that's a spare that is off," he said. "We should be able to easily go another year with the current gyros we have."

Hubble's batteries currently are operating at half their rated capacity. While that is sufficient for normal operations, engineers have no idea how long they will last. "Nobody has ever operated nickel-hydrogen batters in orbit as long as Hubble has," Burch said. "The way we use the batteries, we've been able to get smarter and come up with a better regimen for operating them on a daily basis. But that still doesn't get around the fact that they're well past their design lifetime. The prudent thing to do is replace them. But I think we'll be fine with batteries for the next several months."

As for the no-longer-redundant science data handling subsystem aboard Hubble, "I am very confident the B side will continue to operate normally," Burch said.


05:00 PM, 10/23/08: Endeavour hauled from pad 39B to 39A

The shuttle Endeavour, bolted to a mobile launch platform perched atop one of NASA's powerful crawler-transporters, was hauled off pad 39B at the Kennedy Space Center today and moved to nearby pad 39A for work to ready the ship for blastoff Nov. 14 on a space station resupply and servicing mission. The move came two days earlier than originally planned because of approaching bad weather.

Endeavour was hauled to 39B in late August to serve as a rescue vehicle for the shuttle Atlantis, at that time scheduled for launch from pad 39A on a Hubble Space Telescope servicing mission Oct. 14. But the Sept. 27 failure of an electrical component aboard the telescope forced NASA managers to delay the servicing mission to mid February at the earliest.

As a result, flight planners decided to press ahead with Endeavour's space station flight. Pad 39B is being modified to support launches of the Ares 1 rocket that ultimately will replace the shuttle and Endeavour had to be moved to 39A because of payload processing issues. Endeavour's payload - a supply module and other equipment - was moved to the pad Wednesday.

Endeavour's crew - commander Chris Ferguson, pilot Eric Boe, Heidemarie Stefanyshyn-Piper, Stephen Bowen, Donald Pettit, Robert "Shane" Kimbrough and space station flight engineer Sandra Magnus - is scheduled to fly to Florida Sunday to review emergency procedures and participate in a dress-rehearsal countdown next Wednesday.

If all goes well, Endeavour's countdown will begin at 10 p.m. on Nov. 11, for a launch attempt at 7:55:31 p.m. on Nov. 14.


3:45 PM, 10/23/08: Hubble engineers restart payload computer; gear up for instrument power up in wake of glitches last week

Engineers believe they understand what caused isolated problems during restart of the Hubble Space Telescope's science instruments last week in the wake of an earlier electrical glitch. They have successfully restarted Hubble's B-side payload computer, officials said today, and hope to bring the first of the telescope's science instruments back on line this weekend.

The Hubble trouble began Sept. 27 when the telescope's control unit and science data formatter, or CU/SDF-A, suffered a "hard" failure, preventing ground controllers from receiving data from the science instruments. The A and B channels of the redundant science instrument data handing system are located on the same electronics tray and NASA managers decided to replace the entire unit with a flight spare to restore lost redundancy.

But the flight spare must be tested and recertified, forcing NASA to delay the shuttle Atlantis' launch on Hubble Servicing Mission 4, or SM-4, from mid October to mid February at the earliest.

In the meantime, Hubble managers wanted to restart the telescope's science instruments by reconfiguring six components in the observatory's data management system and five in the science instrument command and control system. Several of the components in question had not been turned on since launch in 1990.

The initial stages of the complex restart procedure went smoothly last week and the B-side science instrument computer powered up normally. But hours later, during re-activation of the Advanced Camera for Surveys solar blind channel, seemingly improper voltage levels triggered an abort. Later, the B-side science computer and science data formatter suffered simultaneous resets for unknown reasons. At the time, engineers did not know if the two events were related.

Art Whipple, manager of the Hubble Systems Management Office at the Goddard Space Flight Center, said today engineers believe they understand what happened - and why - and after a thorough review, managers gave the engineering team permission to attempt another restart.

"One week ago, Hubble experienced two anomalous events at the end of an otherwise nominal reconfiguration to bring on line several backup components to restore our ability to take data with the science instruments," Whipple said. "The first event was the suspension of the Advanced Camera for Surveys on the afternoon of Oct. 16. The second event was the safing of the science payload later that evening. We've spent the last week supporting a detailed review of all data related to both events as well as a thorough assessment of all other systems on the spacecraft. And we're now ready to resume recovery of the science payload and if successful, science operations.

The Advanced Camera for Surveys, installed in 2002, suffered an earlier failure that knocked out its visible light wide-field and high-resolution cameras. Only its solar blind channel, which is sensitive to ultraviolet light, is still in operation. The Atlantis astronauts hope to repair the ACS during the upcoming servicing mission.

Whipple said the ACS solar blind channel power-up abort "was caused by a software test that runs in the ACS microprocessor and it tripped before a parallel data collection application had time to collect sufficient valid data."

"The engineering data clearly shows there were no actual problems with the ACS power supply at the time of the suspension," Whipple said. "Relative timing of these two software processes has always been tight and recent changes to the software to support the planned SM-4 ACS repair, as well as resetting of the onboard master clock that was a part of last week's reconfiguration, just made the timing too tight. The team will correct this problem by changes to the timing of the activation of the ACS software and will use this revision for all future ACS observations. We expect to resume science observations with the ACS solar blind channel later next week.

"Safing of the science payload was caused by a transient electrical event that simultaneously caused the reset of the (B-side) command unit science data formatter and the NASA standard spacecraft computer in the science instrument command and data handling system. That event was most likely caused by a momentary short or open circuit subsequently cleared. Events of these kind are not uncommon in electrical components that have been powered off for long periods of time and it is possible we may see another event of this type in the future."

Whipple said as far as the engineering team can tell from telemetry, "there does not appear to be any permanent damage. There was no harm done by this event to any other systems on the spacecraft."

"Following detailed review of these events, as well as the risk and benefits of resuming recovery of the science payload,, approvals were given ... to bring the SIC&DH back up on the B side," Whipple said. "This was accomplished today, shortly after 1 p.m. Eastern time. The NSSC is back up and running. If the NSSC continues to operate normally, science operations will resume with Wide Field Planetary Camera 2 this weekend and ACS later (next) week."

As of this writing, NASA is working toward a possible launch of Atlantis around Feb. 17. But that assumes the spare science instrument computer hardware undergoing tests at Goddard checks out and no other major problems crop up. Other possible launch targets include March and May. Bill Gerstenmaier, chief of NASA space operations, and Ed Weiler, director of space science, plan to meet Nov. 5 to review testing and launch readiness. A firm launch target date is expected shortly thereafter.


4:15 PM, 10/21/08: Engineers not yet sure what to do about Hubble glitches

After a weekend of troubleshooting, engineers at NASA's Goddard Space Flight Center have not yet pinned down the cause of two glitches last week that prevented restart of the Hubble Space Telescope's science instruments, officials said today.

The restart, switching instrument control to a backup payload computer and components, was required because of a failure in the A channel of the telescope's control unit and science data formatter, or CU/SDF-A, on Sept. 27. To restore the lost redundancy, NASA managers decided to delay the shuttle Atlantis' planned Oct. 14 launch on a final Hubble servicing mission, known as SM-4. That flight now is targeted for no earlier than mid February.

In the meantime, Hubble managers wanted to restart the telescope's science instruments by reconfiguring six components in the observatory's data management system and five in the instrument command and control system. Several of the components in question had not been turned on since launch in 1990.

The initial stages of the complex restart procedure went smoothly, but improper voltage levels were seen in one of the instruments, aborting the startup sequence. Later, the data management subsystem computer also suffered an unexpected glitch.

"On Monday, October 20, engineers at NASA’s Goddard Space Flight Center met to discuss their next steps toward resolving two anomalies which caused the B-side of the Science Instrument Control and Data Handling System (SI C&DH-B) and the Advanced Camera for Surveys (ACS) Solar Blind Channel (SBC) to return to a 'safe hold' status on October 16," NASA said today in a status report.

Over the weekend, "the Hubble team continued detailed reviews of all the data available when last week’s anomalies occurred. A suspect 8-volt power source within the SBC's low voltage power supply (LVPS) reached its nominal output value just after failure of an internal check monitoring its health. Hubble engineers are evaluating alternative procedures and determining whether another attempt to restart the LVPS presents a risk to the instrument or to the planned SM-4 repair of ACS's other cameras."

The Advanced Camera for Surveys, installed in 2002, suffered an earlier failure that knocked out its visible light wide-field and high-resolution cameras. Only its solar blind channel, which is sensitive to ultraviolet light, is still in operation. The Atlantis astronauts hope to repair the ACS during the upcoming servicing mission.

In the meantime, before engineers can restart the solar blind channel - assuming they can resolve the voltage anomaly - they must first coax the B-side science instrument command and data handling system back into operation.

"Intensive study of the SI C&DH-B shutdown also continues," today's status report said. "Analyses done thus far suggest that an electrical event of unknown origin and characteristics caused a reset of both the Control Unit/Science Data Formatter-B (CU/SDF-B) and the NASA Standard Spacecraft Computer-1 (NSSC-1) Central Processing Module-B (CPM-B). Both of these modules were activated on-orbit for the first time on October 15. Additional analyses and a risk assessment of SI C&DH-B reactivation have begun."


6:00 PM, 10/20/08: Atlantis moved back to VAB; Endeavour rollover from pad 39B on tap Friday

The space shuttle Atlantis, its mission to service the Hubble Space Telescope on hold, was hauled off pad 39A at the Kennedy Space Center and back to the Vehicle Assembly Building today, clearing the way for the shuttle Endeavour to take its place this weekend.

Endeavour, scheduled for launch Nov. 14 on a space station resupply mission, currently is mounted atop nearby pad 39B where it was on standby for use as an emergency rescue vehicle for the Hubble crew. With that flight on hold until mid February at the earliest, Endeavour's payload will be moved from a processing facility to pad 39A on Wednesday and the shuttle will be rolled over Saturday.

The goals of the year's final shuttle flight are to deliver equipment and supplies to the space station, including water recycling gear, a second toilet, a second galley and astronaut sleep stations to permit the lab crew to expand from three to six next year. The shuttle astronauts also will attempt to lubricate and clean the station's solar array rotary joints.

The right-side joint has suffered extensive degradation that prevents it from automatically tracking the sun. The astronauts plan to clean and lubricate the starboard mechanism and lubricate the left-side joint as a preventive measure.

Endeavour's crew - commander Chris Ferguson, pilot Eric Boe, Heidemarie Stefanyshyn-Piper, Stephen Bowen, Donald Pettit, Robert "Shane" Kimbrough and space station flight engineer Sandra Magnus - are scheduled to fly to Florida Sunday to review emergency procedures and participate in a dress-rehearsal countdown next Wednesday.

If all goes well, Endeavour's countdown will begin at 10 p.m. on Nov. 11, setting up a launch attempt at 7:55:28 p.m. on Nov. 14.


12:45 PM, 10/17/08: Initial Hubble reboot goes smoothly but anomalies interrupt reactivation (UPDATED at 5:45 p.m. with quotes and details from media teleconference)

Work to switch the Hubble Space Telescope to a backup science data management system after a component failed last month has been interrupted by a pair of on-board glitches during the restart process, officials said today. Engineers do not yet know if the anomalies are related, whether any actual hardware failures are involved or even whether the data management reconfiguration played a role. But they are hopeful analysis of telemetry and computer logs will help them resolve the issue and resume normal science operations.

"The operations team is working diligently to understand the cause and options for proceeding," said Jon Morse, director of the astrophysics division at NASA headquarters. "We remain optimistic at this time for recovering full science operations. But even the best laid plans can encounter some unanticipated difficulties."

The original failure occurred Sept. 27 as NASA was preparing to launch the shuttle Atlantis Oct. 14 on a long-awaited servicing mission. Channel A of the telescope's control unit science data formatter, or CU/SDF-A, began acting erratically and the telescope's main flight computer, following pre-programmed instructions, "safed" the payload computer and science instruments.

An attempt by ground controllers to reset the formatter was not successful and engineers quickly determined the box had suffered a "hard" failure. With the formatter out of action, data from Hubble's operational science instruments could not be relayed to the ground.

The shuttle flight was delayed to mid February at the earliest to give engineers time to flight qualify a spare science instrument control and data handling system, a box that contains both A- and B-side electronics. In the meantime, engineers at the Goddard Space Flight Center in Greenbelt, Md., decided to switch Hubble over to its current B-side data management system to restore science operations. Those components have not been powered up since launch in 1990.

The switchover began Wednesday. Telemetry from the telescope indicated the initial transition went smoothly. Wednesday night, engineers turned on the B-side science instrument control and data handling system, which includes the B-side data formatter. They then confirmed the Wide Field Planetary Camera 2, the one operational channel of the Advanced Camera for Surveys and the Near Infrared Camera and Multi-Object Spectrometer, or NICMOS, were able to communicate with the B-side SI C&DH system. The instruments then were put back in safe mode pending commands to switch control to the SIC&DH.

Thursday, engineers tried to bring the science instruments back on line. That's when the first of two problems developed.

"On Wednesday, engineers at the Goddard Space Flight Center reconfigured six components of the Hubble data management system and five components in the science instrument command and data handling system to use their redundant, or what we sometimes call the B side," said Art Whipple, manager of the Hubble Systems Management Office at Goddard. "This work was to work around a failure that occurred on Sept. 27 in the side-A science data formatter, which is a part of that SIC&DH system. It resulted in a cessation of all science observations except for astrometry, which are done with the fine guidance sensors that don't go through the SIC&DH.

"The reconfiguration proceeded nominally and the Hubble resumed the science timeline at noon Eastern time on Thursday. The first activities out of that onboard science timeline were the commanding of the science instruments from their 'safe' to 'operate' mode. This occurred nominally for the Wide Field Planetary Camera 2 and for the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). However, an anomaly occurred during the last steps of the commanding to the Advanced Camera for Surveys."

The Advanced Camera for Surveys, installed in 2002, suffered an earlier failure that knocked out its visible light wide-field and high-resolution cameras. Only its solar blind channel, which is sensitive to ultraviolet light, is still in operation. The Atlantis astronauts hope to repair the ACS during the upcoming servicing mission.

"At 1:30 p.m. Eastern (Thursday), when the low-voltage power supply to the ACS solar blind channel was commanded on, software that was running in the microprocessor in ACS detected an incorrect voltage level in the SBC and suspended ACS," Whipple said. "Then, at 5:14 p.m., the Hubble spacecraft computer, the 486, sensed the loss of a keep-alive signal from the NASA standard spacecraft computer in the C&DH and correctly responded by safing the SIC&DH and the science instruments.

"At this time, it's not known if these two events were related. The investigation into both anomalies is underway. All the data's been collected and it's being analyzed here at Goddard. The science instruments will remain in safe mode until the SIC&DH issue is resolved. All other systems on the spacecraft are performing nominally."

Asked if the telemetry had shed any light on what sort of problem - hardware failure, commanding error or some sort of misconfiguration - might be responsible, Whipple said "we're in the early stages of going through a mountain of data that has been downloaded over the last 24 hours."

"At this point, we are fairly certain, although nothing's been 100 percent ruled out, but we're fairly certain it is not a configuration or a commanding error," he said. "We are not to the point where we can rule out either transient issues or, for that matter, hard failure. We're just not there yet."

The initial fault in the Advanced Camera for Surveys occurred when a computer inside the instrument failed to detect the required 8 volts from the low-voltage power supply. Several hours later, the 486 flight computer, which constantly monitors the status of the payload computer, detected an apparently loss of keep-alive power in the B-side SIC&DH computer.

Whipple said the actual transition to Hubble's B-side science data management system went smoothly, with no apparent problems.

"There really are no changes that we're seeing in any of our other telemetry," he said. "The behavior of those six data management system components we switched over has been absolutely perfect so far."

But, he added, "we changed a number of things in the configuration of the spacecraft. It was not unexpected that there might be issues. This is, in fact, one of the contingency cases we thought a great deal about ahead of time and we're not totally unprepared for. ... We expect we will work through it, we will be back up and doing science between now and the servicing mission. The team is doing well. I can't tell you they'll get the entire weekend off, but we're cognizant of the fact that this is a marathon, not a sprint. It's important that we do things right, rather than fast."


3:35 PM, 10/14/08: Engineers gear up for critical commanding to switch Hubble to backup electronics After two weeks of engineering reviews and discussions, NASA managers have decided to press ahead with plans to put the Hubble Space Telescope into electronic hibernation Wednesday to carry out what amounts to long-distance neurosurgery. To work around the failure of a science data formatter that shut down science operations late last month, the engineering team will reconfigure Hubble to work with redundant data management subsystem components that have not been powered up since launch some 18 years ago.

"It is obviously a possibility that things will not come up," said Art Whipple, manager of the Hubble Space Telescope Systems Management office at the Goddard Spaceflight Center in Greenbelt, Md.

That's the bad news. The good news is "there is very little aging that goes on with an unpowered component in space."

"It's actually a very benign storage environment," he said. "We have very good confidence this will work. In addition, we have contingency plans built in at each step of the transition where if something does not go the way we expect it to, we'll be able to back out and go down an alternate path."

NASA was in the process of preparing the shuttle Atlantis for launch - the target date was today - when channel A of the telescope's control unit science data formatter, or CU/SDF-A, began acting erratically. The telescope's flight computer, following pre-programmed instructions, then acted to "safe" the payload computer and science instruments. An attempt by ground controllers to reset the formatter was not successful and engineers quickly determined the box had suffered a "hard" failure.

While a backup system was available, NASA managers decided to postpone Atlantis' launch on mission STS-125, also known as Hubble Servicing Mission 4, until mid February at the earliest to give engineers time to test and certify a spare unit, used for ground testing, that will be added to the shuttle manifest.

Whipple said ongoing paperwork reviews have not turned up any show stoppers. Vibration, thermal-vacuum and electromagnetic testing will begin next week and engineers should have a good idea by early November whether February is a real possibility for launch. In the meantime, program managers decided to go ahead and attempt a switchover to side B of the telescope's data management subsystem to restore normal science operations.

"The Hubble team has developed and tested the process for switching the Hubble Space Telescope observatory over to its side B and received the necessary approvals for proceeding," Jon Morse, director of NASA's astrophysics division, told reporters today. "The process will commence tomorrow morning and it's expected to take a couple of days to bring the observatory back to science operations.

"Switching to side B accomplishes two main things. One is to recover Hubble's science productivity using its main science instruments, especially the Wide Field and Planetary Camera 2 and the solar blind channel of the Advanced Camera for Surveys. It will also give the team the opportunity to restart the NICMOS cryo cooler, to bring that NICMOS infrared camera back to operational status. Another benefit is to test the side B functionality of the observatory in order to verify HST's redundancy. Restoring that redundancy was the main reason for delaying STS-125."

The transition to side B will involve 40 to 50 engineers at Goddard. Commanding will begin around 6 a.m. Wednesday, with the most critical phase between 8:30 a.m. and 11 a.m. After that, the team will work to bring Hubble out of an induced coma, or "safe mode." If all goes well, Hubble should be back in normal science mode early Friday.

Here's how Whipple described the initial failure and the transition procedure:

"On Sept. 27, just a little over two weeks before the planned October 14th launch of SM-4, the main flight computer on Hubble detected an error signal from the science instrument command and data handling subsystem and correctly responded by putting the SIC&DH and the four science instruments into protective safe mode. The failure was quickly isolated to a hard failure in one of the science data formatters in the SIC&DH. There are two formatters in that unit, one that failed and a second that has been kept as an unpowered backup since Hubble was launched in April 1990.

"There are no indications that this failure affected any other components in the SIC&DH, the science instruments or, in fact, anywhere else on the spacecraft. In its current configuration, Hubble can perform all of its normal health, safety and housekeeping functions but it can only perform astrometry science with the fine guidance sensors, since they do not communicate through the SIC&DH.

"Starting on Wednesday, we will reconfigure Hubble to use the redundant science data formatter in the SIC&DH and six redundant associated components in the spacecraft data management system to restore science operations. Five of the six redundant components in this data management system that will be brought on line have also not been powered since 1990. The command procedures to accomplish this transition have been thoroughly tested. ... So beginning early tomorrow morning, engineers at Goddard will start commanding the reconfiguration and we expect to see the first science data by midnight on Thursday with Hubble back in its science mode on Friday morning."

"Over the last few weeks, the HST operations team has worked hard to be sure the procedures are in place to accomplish an efficient and safe transition. We are confident that all preparations are complete and the team is ready to go."

Because of the way Hubble was designed in the 1970s, it isn't possible to simply power up the B side data formatter and add it to the A side electronics. Instead, ground controllers must power down the telescope and switch over a half-dozen other components as well.

"When we talk about bringing up the B side of the science data formatter, it's actually in a component with the control unit," Whipple said. "You sometimes see people refer to the CU/SDF, that's the box that will be on the B side. That involves the redundant power bus into the SIC&DH and with that comes the use of the redundant computer in that SIC&DH. You can actually run either computer from either bus, but the most straight forward configuration is running it straight through the B side. So that's how the SIC&DH will be configured.

"Because of the way the science payload is wired to the spacecraft bus and the whole data management system on the spacecraft, there are six other boxes that have nothing to do with the science payload - it's a telemetry format control module, a timing interface module, a communications module, a command data interface module, a data interface unit interface and then data interface unit No. 5 - all of those boxes, just because of the way the architecture was designed in the 1970s, are not fully cross-strapped. ... so those six boxes need to come over with the CU/SDF."

Assuming the switchover works, the telescope will again be able to downlink photos from the Wide Field Planetary Camera 2 and the infrared NICMOS camera. The observatory's other two major instruments, the partially operational Advanced Camera for Surveys and the Space Telescope Infrared Spectrograph, are awaiting repairs during the upcoming servicing mission.

During the five-spacewalk mission, the Atlantis astronauts also plan to install two new science instruments, six new batteries, six stabilizing gyroscopes, a fine guidance sensor and replacement insulation. The upgrades are expected to extend Hubble's life at least five years. It's not yet clear where the computer unit swap out needed to restore redundancy in the science data management subsystem will be inserted in the timeline.

Shuttle engineers are currently planning for a possible launch around Feb. 17. But space station operations, the readiness of the new computer unit and a variety of other factors could force NASA to delay Hubble Servicing Mission 4 to early May.

"We think in the first week or two in November we will have a much better handle on the actual state of the hardware," Whipple said. "The paperwork says February should be supportable, but we should have much higher confidence (in November)."


02:45 PM, 10/3/08: NASA shoots for Nov. 14 Endeavour launch; station crew ready for visitors (UPDATED at 5:30 p.m.; rollback Oct. 20)

Shuttle program managers are now targeting Nov. 14 for launch of the Endeavour on a space station repair and resupply mission. No target dates have yet been set for shuttle Atlantis' launch on a now-delayed flight to service the Hubble Space Telescope, but it appears the earliest possible launch slot is mid February.

Under that scenario, the shuttle Discovery would serve as the Hubble crew's rescue vehicle. As a result, Discovery's launch on a high priority station assembly flight, currently targeted for Feb. 12, would be delayed. But NASA managers are considering a variety of options, including one that would keep the February station flight on track and instead delay Hubble Servicing Mission 4 to early May. Mission managers hope to have a better idea about how to proceed after additional assessments over the next week or so.

Atlantis had been scheduled for launch Oct. 14 from pad 39A, but the flight was put on hold earlier this week after a critical electronic component aboard Hubble malfunctioned, preventing science data from reaching the ground. The component is part of a redundant computer system and a backup channel is available. But with the failure of the A-side electronics, Hubble could be knocked out of action for good by a subsequent failure. NASA managers opted to delay Atlantis to give engineers time to prepare replacement hardware.

Engineers at the Goddard Spaceflight Center in Greenbelt, Md., currently are reviewing the complex procedures needed to switch Hubble over to its B-side data management system, which has not been activated since before launch in 1990. It's not yet clear when the switchover will be attempted. Because of the critical nature of the operation, Hubble managers want to make sure the procedure is solid before it is implemented.

At the Kennedy Space Center, shuttle engineers are setting their sights on getting Endeavour ready for flight, preparing to remove the Hubble payload from Atlantis' cargo bay so the shuttle can be hauled back to the Vehicle Assembly Building Oct. 20. Endeavour, the Atlantis rescue vehicle, is mounted atop pad 39B. The current plan calls for Endeavour to be moved from pad 39B to 39A on Oct. 25 for final preparations.

Shuttle program managers plan to hold a flight readiness review Oct. 21 and 22, followed by an executive-level review Oct. 30. Endeavour's crew, meanwhile, plans to fly to the Kennedy Space Center on Oct. 26 to review emergency procedures and participate in a dress-rehearsal countdown on Oct. 29.

If all goes well, the countdown will begin for real on Nov. 11, setting up a launch attempt at 7:55 p.m. on Nov. 14. Docking is expected around 5:10 p.m. on Nov. 16. Four spacewalks are planned, each one starting around 1:50 p.m., on Nov. 18, 20, 22 and 24. Undocking is expected around 10;49 a.m. on Nov. 27 with landing back at the Kennedy Space Center targeted for 2:18 p.m. on Nov. 29.

In the near term, the Russian space program is gearing up to launch a fresh crew to the space station. Expedition 18 commander Mike Fincke, flight engineer Yuri Lonchakov and Richard Garriott, a space tourist, are scheduled for launch from the Baikonur Cosmodrome in Kazakhstan at 3:01 a.m. EDT on Oct. 12 aboard the Soyuz TMA-13 spacecraft. Garriott, the son of former Skylab and shuttle astronaut Owen Garriott, will be the first second-generation American to fly in space.

Fincke and Lonchakov will replace Expedition 17 commander Sergey Volkov and flight engineer Oleg Kononenko, who were launched to the station April 8 aboard the Soyuz TMA-12 spacecraft. Volkov, Kononenko and Garriott are scheduled to undock from the station around 8:20 p.m. on Oct. 23 for a landing in Kazakhstan three hours later, at 11:46 p.m. EDT.

The two previous Soyuz entries ran into problems that triggered steep, off-course landings. Russian engineers believe the electrical environment around the station caused arcing that, in turn, affected specific pryo bolts used to separate the Soyuz crew module just before atmospheric entry.

Volkov and Kononenko removed a pyro bolt from the TMA-12 spacecraft during a July 10 spacewalk and plan to bring it back to Earth for a detailed analysis. With the bolt removed, Russian engineers believe the TMA-12 vehicle will separate normally.

"They sent us a report and they assured us that everything should be OK," Volkov told CBS News today. "Of course, we've done a spacewalk to remove this pyro bolt that they thought might be causing the problem for previous crews' landing. They made some mathematical calculation for the re-entry into the atmosphere. And they said everything should be OK."

Expedition 17 flight engineer Gregory Chamitoff, launched to the station aboard a space shuttle on May 31, will remain aboard the lab complex with Fincke and Lonchakov when Volkov and Kononenko depart. Chamitoff is scheduled to return to Earth aboard Endeavour in November, taking the seat of his replacement, Expedition 18 flight engineer Sandra Magnus.

Chamitoff said today he was excited at the prospect of visitors after four months in space.

"We're ready to have them on board, we're very excited they're coming," he said of the Expedition 18 crew. "Of course, I'm going to miss these guys very much. We've had a great time together for a long time. If we were ... to go to Mars and back, we'd have done great together I think. But we're looking forward to our friends that are coming up. I can't wait to welcome them here. And it's the same for the shuttle, too. We've done a lot of work to prepare for the shuttle and all the shuttle's going to do here, all the stuff that has to be off loaded and all the stuff that has to be loaded on the shuttle. We're looking forward to it."

Outgoing station astronauts typically spend several days briefing their replacements on the intricacies of station operation. Fincke is a station veteran, but the lab has changed considerably since he was there in 2004.

"It'll be easier for him to come on board for the second time," Chamitoff said. "I won't have to worry about showing him all the ropes, he'll know most of everything. But since he was here, we've added many modules to the space station. Everything behind me, actually, is brand new since he was here. So two spectacular laboratories. ... So there's a lot to show him, how we do everything and what's going on in those laboratories. So there's plenty of us to talk about."

Including politics. Chamitoff said he's been able to watch presidential debates and speeches from the Republican and Democratic conventions that were beamed up from mission control. Both Fincke and Chamitoff will cast their votes from orbit via computers aboard the station.

"It's great that we're able to do that, it's really important to vote, especially this time," Chamitoff said. "There's a lot going on on the ground. We've been following and we're both really glad we're going to be able to vote. It's basically like an absentee ballot, an electronic ballot especially set up between NASA and the county. We fill it out electronically, send it down and then the county records it. They actually convert it to a paper ballot. Anyway, this is all in place and we should be able to vote. So it's great."

Chamitoff rode out Hurricane Ike aboard the space station. The storm was so huge, he said, it wouldn't fit in his camera's field of view.

"Our hearts go out to everybody in Houston right now because we know it's a very big effort now to recover for everyone and a lot of folks have a lot that they have lost," he said. Because mission control and the Johnson Space Center shut down the week of the storm, "we didn't really see much of what happened other than what we heard directly from the control center until afterwards. And it's devastating to see everything that happened there, really devastating. But my family could leave town. Our house does have some roof damage, but of course, nothing compared to what many other people have had to deal with."

He said the crew tracked Ike's progress as the station flew over and "we certainly saw the hurricane before it approached and hit Houston."

"You know, this hurricane was so massive," Chamitoff marveled. "Other ones we were able to sort of see clear borders around the hurricane and the center and see kind of the flow of clouds entrained into the hurricane. This one was so difficult to get the whole thing in any camera lens. It was unbelievable. And of course, afterwards now, when we're flying over with a high zoom lens, it is possible for us to see the changes there. I've been able to see Galveston and taken some pictures. There's clearly missing structures along the coast. Those pictures will kind of be good to help look at exactly what happened, before and after."


02:30 PM, 10/01/08: Setting up STS-126 page

With launch of the shuttle Atlantis on hold, mission planners are pressing ahead with preparations for launching the shuttle Endeavour on mission STS-126, a space station assembly flight, in mid November. Program managers are assessing a variety of options and no firm launch targets have been set. But it appears Endeavour is heading for a launch around Nov. 14. The schedule for Atlantis is less certain. The flight is expected to slip to mid February at the earliest because of an equipment failure aboard the Hubble Space Telescope and a decision earlier this week to add replacement hardware to mission STS-125.

This page has been udpated to shift the focus to STS-126. An updated flight plan, personnel list, launch windows chart, crew seating and links to astronaut bios are available on the CBS News STS-126 Quick-Look page:

http://www.cbsnews.com/network/news/space/currentglance.html

An updated flight plan for Atlantis and mission STS-125 also is available on the Quick-Look page, reflecting a launch around 6:50 a.m. on Feb. 17. This date is little more than a "guesstimate" at this point and the timeline is provided primarly to give readers a ballpark idea about when major events would occur for a mid-February launch.

Both flight plans and personnel lists are available in SpaceCalc_126, which has been updated and is available on the downloads page:

http://www.cbsnews.com/network/news/space/downloads.html


8:00 PM, 9/29/08: NASA assesses February - or later - launch for Hubble servicing mission; optimistic new repair can be added to busy mission

Living up to its "Perils of Pauline" heritage, a critical equipment failure aboard the Hubble Space Telescope on the eve of a long-awaited fifth and final shuttle servicing mission put astronomical observations on hold and forced NASA managers today to delay the mid-October flight of Atlantis. Pending an engineering review, the long-awaited servicing mission is expected to slip from Oct. 14 to mid February - and possibly later - to give engineers and astronauts time to shoehorn replacement hardware into an already challenging five-spacewalk mission.

"Barring some unforeseen circumstance ... our plan right now is to take the delay and put up the new hardware so we can keep Hubble going as long as possible," said Ed Weiler, NASA's associate administrator for space science. "If we're going to spend the money and take all the risk involved in a shuttle mission, we want to be sure we leave Hubble as healthy as we possibly can and potentially lasting for five or 10 more years."

Weiler said NASA was lucky the electronics failure occurred now, on the eve of launch, and not after the final servicing mission was over.

"Think about if this failure had occurred two weeks after the servicing mission," he told reporters in an afternoon teleconference. "We'd have several single point failure, we could have lost the mission in six, 12, 18 months. So in some sense, if this had to happen it couldn't have happened at a better time. ... So I'm trying to look at the glass as half full today and I think it IS half full for us."

Shuttle Program Manager John Shannon said he expects a decision on how to proceed by the end of next week. Assuming the Hubble mission is, in fact, delayed to next year, NASA will press ahead with launch of the shuttle Endeavour on a space station assembly mission around Nov. 14, two days earlier than currently planned.

Endeavour is stacked atop pad 39B at the Kennedy Space Center to serve as a quick-response rescue vehicle for the Hubble astronauts in case of any post-launch problems that might prevent a safe re-entry. With a decision to delay the Hubble flight, Atlantis would be hauled off pad 39A and moved back to the Vehicle Assembly Building. Endeavour then would be moved to 39A for normal launch processing. NASA is in the process of converting pad 39B for use by the Ares rockets that will replace the shuttle. While the pad could be used to support Endeavour's launch on a rescue mission, it's payload changeout room is no longer capable of normal processing.

Whenever Atlantis takes off on mission STS-125, Endeavour will no longer be available for rescue duty. For a Hubble flight in February, the shuttle Discovery, currently scheduled for launch Feb. 12 on a mission to deliver a final set of solar arrays to the space station, would be pressed into service. That flight is known as STS-119.

But Shannon must take into account how the Hubble flight would fit into the overall manifest. The Russians plan two Soyuz launches to the space station next spring and temperature constraints due to the station's orbit will preclude shuttle visits for several weeks in that timeframe. One option would be to delay the Hubble flight until after Discovery's station assembly mission. In that case, Endeavour, scheduled for another launch next May, could once again serve as the rescue vehicle.

"There is a time starting on March 13 and ending May 28 where we have two Soyuz launches and a significant beta cutout whereas the Hubble mission is not constrained by any of that," Shannon said. "So we will consider that once we know more about the Hubble need date. If we could put the Hubble in and fly STS-119 before that (first) Soyuz, that would be good. If it looks like Hubble needs a little more time than that, then it's very possible we could fly 119 first, let Hubble fly sometime in that Soyuz and beta cutout with (Endeavour) as the launch-on-need vehicle."

The problem aboard Hubble cropped up shortly after 8 p.m. Saturday when channel A of the telescope's control unit/science data formatter, or CU/SDF-A, began acting erratically. The telescope's flight computer, following pre-programmed instructions, then acted to "safe" the payload computer and science instruments. An attempt by ground controllers to reset the formatter was not successful. Troubleshooting continues, but engineers are not optimistic.

The telescope is not in any danger, but science operations are on hold until engineers can reconfigure the observatory to use channel B of the control unit/science data formatter. Engineers plan to make the switchover Thursday or Friday, after a detailed readiness review.

"All the testing and all the efforts so far to restore (the A-side electronics) indicates it has totally failed," said Hubble Program Manager Preston Burch. "Our only option at this point is to switch over to science data formatter B, which is the redundant channel. Unfortunately, switching to that side will require the switch over of the spacecraft data management system to the B side as well. ... So this is a major event for Hubble."

The backup, or "B side," of the data management system has not been powered up since the telescope was launched in 1990. Even if it works - and if five instrument subsystems successfully make the transition to their own B channels - NASA would still be faced with a loss of redundancy in a critical system and a subsequent failure would permanently disable the observatory.

"The transition to side B operations is complex," NASA said in a statement. "It requires that five other modules used in managing data also be switched to their B-side systems. The B-sides of these modules last were activated during ground tests in the late 1980's and/or early 1990, prior to launch. The Hubble operations team has begun work on the Side B transition and believes it will be ready to reconfigure Hubble later this week. The transition will happen after the team completes a readiness review."

Given CU/SDF-A worked normally for nearly two decades, one could argue the backup channel should work as required for years to come. But senior managers do not want to risk mounting a costly servicing mission and then leave the telescope without redundancy and no chance to carry out an additional servicing mission before the shuttle is retired in 2010.

"If we go that route, just go to side B, we would be left with a system that has several single point failures and that would pose a risk to the mission," Weiler said. "By going ahead and accepting a delay of perhaps several months, we can actually get our SIC&DH (science instruments command and data handling) spare unit tested and ready to go. And if we can put that in there sometime in the winter, we would now have an observatory that was again doubly redundant, that is, it would have backup systems, it wouldn't have single point failures in it. That's the reason we're looking at accepting this several months delay to buy back that redundancy we used to have with a fully functional side A."

A spare science instruments command and data handling system, which includes the needed control unit/science data formatter, is available at the Goddard Space Flight Center in Greenbelt, Md. But it is not flight qualified and it has not been powered on since 2001. Extensive testing and checkout will be required to upgrade it to flight status. The box weighs about 135 pounds and measures 21.5-by-32.5-by-9.5 inches. It will be mounted on the side of a payload carrier in Atlantis' cargo bay for the ride up to Hubble. Burch said the shuttle can easily accommodate the additional hardware and nothing will have to be removed to make room.

Installation of the box is expected to take about two hours to complete. The unit would be attached to the door of electronics bay No. 10 with 10 bolts and one electrical connector. Engineers have not yet decided where the work might go in the already tight spacewalk timeline.

But Burch said it's possible the additional task can be added to the crew's timeline without losing any other already planned task. The repair of Hubble's Advanced Camera for Surveys, for example, is currently spread over two spacewalks, EVAs 3 and 5. But if the work is completed in the first of those two excursions, the crew would be able to install the new data formatter hardware during the ACS block of time in the second EVA.

"Given the fact that we think this job can be done in under two hours, there is a possibility ... if he's able to complete the ACS repair on EVA day 3, that frees up a substantial amount of time on EVA day 5. So in theory, this may be a doable thing for us to have our cake and eat it too. But a lot of things will have to go right. And we certainly don't want to over extend the crew."


12:00 PM, 9/29/08: Hubble science data control system fails; NASA assesses shuttle servicing options (UPDATED at 2:30 p.m. with launch delay)

A science data control system aboard the Hubble Space Telescope failed Saturday, preventing the observatory from relaying data to the ground and effectively ending science operations until the observatory can be switched over to a backup unit late this week. With no redundancy left in such a critical system, NASA managers decided today to delay the planned Oct. 14 launch of the shuttle Atlantis on a Hubble servicing mission. It is not yet clear how long it will take to resolve the issue, but sources say replacing the channel A electronics of the control unit/science data formatter likely would push launch to January or February.

"Fixing the problem will result in delaying next month's Hubble servicing mission," NASA said on a web page announcing an afternoon media teleconference to discuss the problem and NASA's options.

The telescope is not in any danger, but science operations have been suspended until engineers can reconfigure the observatory to use channel B of the control unit/science data formatter, or CU/SDF-B. The backup channel has not been powered up since the telescope was launched in 1990. Even if it works - and if multiple subsystems successfully make the transition - NASA would still be faced with a loss of redundancy in a critical system and a subsequent failure would permanently disable the observatory.

Given CU/SDF-A worked normally for nearly two decades, one could argue the backup channel should work as required for years to come. But senior managers do not want to risk mounting a costly servicing mission and then leave the telescope without redundancy and no chance to carry out an additional servicing mission before the shuttle is retired in 2010.

Shuttle mission STS-125, the fifth and final Hubble servicing mission, already has a full plate: five back-to-back spacewalks are planned to install two new science instruments, to repair two others, to install six new gyroscopes, six new batteries, a new fine guidance sensor and new insulation blankets. It is considered one of the most challenging Hubble servicing missions yet attempted.

A spare control unit/science data formatter, used for testing and troubleshooting, is available at the Goddard Space Flight Center in Greenbelt, Md., but it has not been powered on since 2001 and it would require extensive testing and checkout to upgrade it to flight status. Whether the unit could be added to Atlantis' payload complement without bumping something else is not yet known.

Likewise, it's not yet known when Atlantis could be ready for launch if a replacement is ordered. But sources said today the flight likely would slip to January or February, throwing a wrench of sorts into NASA's tightly scripted space station assembly schedule.

If the Hubble flight is, in fact, delayed to next year, NASA likely would press ahead with plans to launch the shuttle Endeavour around Nov. 16 on a space station assembly mission. Endeavour already is mounted atop pad 39B to serve as a quick-response rescue vehicle for Atlantis should the Hubble crew encounter any orbiter problems that might prevent a safe re-entry. It's not yet clear, however, which pad Endeavour would use if the Hubble flight is delayed.

Either way, the shuttle Discovery, now scheduled for launch Feb. 12 on a mission to deliver a final set of solar arrays to the station, would have to replace Endeavour as a rescue vehicle for Atlantis.

In the meantime, NASA managers have postponed a planned executive-level flight readiness review for Atlantis and mission STS-125. A media teleconference to discuss the Hubble failure and possible shuttle launch scenarios is expected later today.


12:25 PM, 9/26/08: Launch window update

Flight controllers have revised the launch time for shuttle Atlantis on Oct. 14. Controllers initially decided to launch the shuttle 10 minutes after the opening of the launch window to improve ascent performance. But a more detailed timeline analysis showed that would require an earlier rendezvous with the Hubble Space Telescope and, as a result, a lower-than-allowable altitude after the OMS-2 orbit adjustment rocket firing. To meet requirements, flight planners moved launch up three minutes to the opening of the second of two "panes" at 10:16:27 p.m. The window will close at 11:11:09 p.m. The launch time is still more than 10 minutes after the opening of the overall launch window, preserving the desired ascent performance margin. The flight plan, rendezvous timeline and launch windows chart posted on the CBS News STS-125 Quick-Look page have been updated to reflect this change.


01:45 PM, 9/24/08: NASA delays next two shuttle missions to make up for time lost to Hurricane Ike

Shuttle program managers today ordered minor delays for the next two shuttle missions - an October flight to service the Hubble Space Telescope and a November space station assembly mission - primarily because of training time lost in the aftermath of Hurricane Ike.

The target launch date for shuttle mission STS-125, the fifth and final planned Hubble servicing mission, will slip from Oct. 10 to 10:19 p.m. EDT on Oct. 14, officials said. Shuttle managers meeting for a program-level flight readiness review also agreed to delay launch of Endeavour on the next mission, STS-126, from Nov. 12 to Nov. 16. Liftoff of that flight would be targeted for around 7:07 p.m.

The new target dates still must be reviewed by senior management, which plans an executive-level readiness review Oct. 2 and 3.

Both delays were blamed on Hurricane Ike, which forced NASA to shut down the Johnson Space Center last week. The Atlantis astronauts, training for one of the most complex Hubble missions yet attempted, missed four underwater spacewalk training runs, two large-scale integrated simulations involving the astronauts and flight controllers and an ascent simulation to practice emergency procedures.

"We had a little bit of room in the final couple of weeks, but all that stuff needs to be done and we have to make it happen before we fly," Atlantis commander Scott Altman told reporters Tuesday.

Altman, pilot Gregory C. Johnson, flight engineer Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good donned pressure suits and strapped in aboard Atlantis today for a dress-rehearsal countdown at pad 39A.

If the new target dates hold up, Atlantis would take off for real at 10:19:20 p.m. on Oct. 14. After a two-day orbital chase, robot arm operator McArthur would grapple the telescope around 9:33 p.m. on Oct. 16.

Five back-to-back spacewalks are planned to install two new science instruments, to repair two others and to install six new gyroscopes, six batteries, a fine guidance sensor and insulation. For an Oct. 14 launch, the spacewalks would begin around 3:30 p.m., with the first on Oct. 17 and the final excursion on Oct. 21.

If all goes well, Hubble would be released around 5:17 p.m. on Oct. 22 and Atlantis would land back at the Kennedy Space Center around 8:07 p.m. on Oct. 25.

The Hubble mission is the only flight on NASA's shuttle manifest that doesn't go to the international space station. Because the telescope is in a different orbit, the Atlantis astronauts cannot seek safe haven aboard the lab complex in case of a major problem that might prevent a safe re-entry.

Even though the odds of such a failure are considered remote, the shuttle Endeavour, hauled to pad 39B late last week, is being prepped for launch on an emergency rescue flight if the unexpected occurs. After Endeavour is cleared for entry, Endeavour will be moved to pad 39A and prepared for launch on a four-spacewalk station assembly flight.

Under the proposed schedule, Endeavour would take off around 7:07 p.m. on Nov. 16 and dock with the space station around 4:40 p.m. on Nov. 18. Four spacewalks are planned, each one starting around 1 p.m., on Nov. 20, 22, 24 and 26. Undocking would be targeted for around 10 a.m. on Nov. 29 with landing on tap the afternoon of Dec. 1.

Updated flight plans reflecting the new target dates are posted on the CBS News STS-125 Quick-Look page.

http://www.cbsnews.com/network/news/space/currentglance.html


11:45 AM, 9/23/08: Shuttle commander says crew needs to make up training lost because of hurricane

Reviewing emergency procedures at the Kennedy Space Center, Atlantis commander Scott Altman said today his crew lost a week of training time because of Hurricane Ike, "so you come to the question of either slipping the launch or cutting out events."

"We're still working with the whole system to balance that," he told reporters at the launch pad. "In the end, I think we're going to try to do most of our training and that, of course, may mean a bit of a slip. But it's being evaluated and we're kind of standing by."

Atlantis is targeted for launch at 12:43:35 a.m. on Oct. 10 to kick off a long-awaited flight to service and upgrade the Hubble Space Telescope. Five back-to-back spacewalks are planned to install two new instruments, to repair two others and to install new gyroscopes, batteries, a fine guidance sensor and insulation.

Altman and his crewmates - pilot Gregory C. Johnson, flight engineer Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good - flew to Florida on Sunday to review launch pad emergency procedures and to participate in a dress-rehearsal countdown Friday.

While that exercise is proceeding, shuttle program managers will meet to discuss a wide variety of issues, from Atlantis' processing and work to ready shuttle Endeavour for a possible rescue flight to the increased threat posed by orbital debris at Hubble's high altitude. They also will review crew training and the impact of Hurricane Ike, which forced NASA to shut down the Johnson Space Center last week. The campus-like facility escaped major damage, but critical training time was lost for the crew, flight controllers and Hubble engineers at the Goddard Space Flight Center in Greenbelt, Md.

Sources say launch is expected to slip a few days, but no final decisions have been made. A recommendation will be forwarded to an executive-level flight readiness review scheduled for Oct. 2 and 3.

"It was seven days, seven events," Altman said of the interrupted training. "Basically four NBL (Neutral Buoyancy Laboratory) runs, practicing the spacewalks; two large-scale integrated simulations with both Goddard and Houston playing together while we trained EVA-5 and rendezvous day. And then we missed an ascent integrated sim where we practice the whole launch routine and how we respond to emergencies. So a lot of important stuff. ... We had a little bit of room in the final couple of weeks, but all that stuff needs to be done and we have to make it happen before we fly.

"We'd like to have all the training as planned. There are a couple of things that I think we could still launch into space without and be fully trained and ready to carry out a successful mission. There are things the crew doesn't need, but the control team on the ground and at Goddard needs to make sure they're fully up to speed. So we're looking at balancing that, who plays when, is the crew involved in everything or do we try to do things a little creatively?"

The two runs in NASA's spacewalk training pool were intended to rehearse complex repairs needed by two instruments aboard Hubble, the Advanced Camera for Surveys and the Space Telescope Infrared Spectrograph. Neither instrument was designed to be serviced in space and the work is considered especially challenging.

Altman, Grunsfeld and Massimino visited Hubble in 2002 as members of the STS-109/Servicing Mission 3B crew. At the time, STS-109 was considered one of the most complex missions ever attempted by a shuttle crew. But Grunsfeld said today Servicing Mission 4 aboard Atlantis will be even more demanding, highlighting the importance of crew training.

"The bottom line to me is this mission is really hard," Grunsfeld said. "After 109, I thought we'd really maxed out what we could do on a space mission. ... This time, we've added a lot of content with (heat shield) inspections. From an EVA standpoint, we've gone from doing heart surgery on Hubble to what is comparable to doing brain surgery on Hubble with the instrument repairs. So this is going to be a very complex mission, it's going to be very hard."

Massimino said the crew will be ready, despite the impact of Hurricane Ike.

"We've been training hard and long and I feel pretty confident we're going to be able to pull those two repairs off," he said. "I think we're ready for them and it's just to be fresh, have it fresh in your mind, we're going to hopefully recover those NBL runs and do a little more training in the simulator. But I think we're as ready as we're ever going to be to do that. Hopefully it'll go as we expect it to. There'll probably be some surprises in there that we didn't anticipate. But I think we're going to be ready to react to those as well."


7:45 PM, 9/22/08: Launch slip likely; shuttle crew preps for countdown test; Endeavour at pad 39B; Hubble payload delivered to pad 39A; launch window update

The Atlantis astronauts are reviewing emergency procedures at the Kennedy Space Center before participating in a dress-rehearsal countdown Wednesday. Launch on a high-profile mission to service and upgrade the Hubble Space Telescope remains targeted for 12:43:35 a.m. Oct. 10, but sources say the flight is expected to slip a few days because of training and hardware processing issues.

A shuttle program-level review is planned later this week. Mission managers will assess the shuttle's readiness, crew training, flight control preparations and the impact of Hurricane Ike on the Johnson Space Center workforce, before making a launch date recommendation to senior NASA managers. An executive-level FRR is scheduled for Oct. 2 and 3.

While the launch target remains Oct. 10, sources said today a slip of two or more days is expected because of lost training time due to the hurricane and the shutdown of the Johnson Space Center last week, as well as payload processing issues at the Kennedy Space Center.

The Atlantis astronauts, who flew to the Kennedy Space Center on Sunday to participate in this week's Terminal Countdown Demonstration Test, or TCDT, were in good spirits and eager to get on with preparations.

"I just wanted to take a minute and tell you all how happy we are to be down here and how great it felt to fly by and see a pad with our vehicle on it pointed up, ready to go," commander Scott Altman told reporters at the shuttle runway. "It's great to be down here and turning our focus from the hurricane that's behind us now to the flight that is in front of us."

Late last week, engineers delayed delivery of Atlantis' payload to the pad because of an insulation contamination issue with an instrument canister. That problem was resolved and the cargo was moved to the pad Saturday night, the day after the shuttle Endeavour was hauled to nearby pad 39B to serve as an emergency rescue vehicle for the Atlantis crew.

Engineers ran into more problems getting the Hubble cargo canister hoisted into pad 39A's payload changeout room, but the work was completed early Monday. The Hubble payload - two new science instruments, new batteries, gyros and other needed hardware - will be installed in Atlantis' cargo bay Tuesday.

Altman and his crewmates - pilot Gregory C. Johnson, flight engineer Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good - will field questions from reporters at the launch pad early Tuesday.

If all goes well, the astronauts will don pressure suits and strap in aboard Atlantis Wednesday for a practice countdown that will end with the simulated ignition and shutdown of the shuttle's main engines.

Mission planners have opted to launch Atlantis 10 minutes after the daily launch window opens to maximize ascent performance. Here is an updated launch windows chart (in Eastern Time):

DATE.......WINDOW OPEN...LAUNCH........WINDOW CLOSE

10/10/08...12:33:35 AM...12:43:35 AM...01:39:51 AM

10/11/08...12:03:54 AM...12:13:54 AM...01:09:13 AM

10/11/08...11:36:45 PM...11:46:45 PM...12:38:36 AM

10/12/08...11:06:08 PM...11:16:08 PM...12:08:02 AM

10/13/08...10:35:33 PM...10:45:33 PM...11:41:47 PM

10/14/08...10:09:20 PM...10:19:20 PM...11:11:09 PM

10/15/08...09:38:41 PM...09:48:41 PM...10:40:34 PM

10/16/08...09:08:05 PM...09:18:05 PM...10:14:23 PM

10/17/08...08:37:30 PM...08:47:30 PM...09:43:43 PM

10/18/08...08:11:16 PM...08:21:16 PM...09:13:06 PM
			
10/19/08...07:40:38 PM...07:50:38 PM...08:42:31 PM


5:20 PM, 9/17/08: Hubble instrument carrier contamination issue assessed; payload delivery delayed at least 24 hours (UPDATED at 11:40 PM with Endeavour rollout delay)

Trouble with a purge system connected to a canister housing fresh batteries and a new camera bound for the Hubble Space Telescope somehow blew insulation into protective bagging around the cargo carrier, officials reported late today. Work to inspect and clean the canister will delay its delivery to the shuttle Atlantis at launch pad 39A by at least 24 hours. While a corresponding launch delay is possible, NASA is sticking with its current Oct. 10 launch target until managers get a better sense of how much lost time can be made up.

"During installation today of the super lightweight interchangeable carrier, the SLIC, what they believe is some insulation around the new batteries we're taking up on that carrier got blown by the purge system up inside the protective bagging," said NASA spokesman Allard Beutel. "So we stopped operations. We're having to unbag that carrier, clean up all the insulation, make sure there's no contamination, rebag it, install it in the canister and take it to the launch pad."

Atlantis is mounted atop pad 39A, being prepared for launch Oct. 10 on a fifth and final mission to service and upgrade the Hubble Space Telescope. The shuttle's crew plans to fly to the Kennedy Space Center on Sunday to review emergency procedures and participate in a dress-rehearsal countdown next Wednesday.

Late today, engineers made finel preparations to haul the shuttle Endeavour from the Vehicle Assembly Building to nearby pad 39B to serve as a rescue vehicle for the Atlantis crew in case of a post-launch problem that might prevent a safe re-entry. Bad weather, however, forced NASA to delay rollout by 24 hours, from early Thursday to early Friday.

Unlike crews bound for the international space station, the Atlantis astronauts cannot seek safe haven aboard the lab complex because Hubble and the station are in different orbits. As a result, NASA Administrator Mike Griffin decided to process Endeavour in parallel for possible rescue duty. Assuming no such flight is required, Endeavour will be moved to pad 39A after Atlantis departs and prepared for launch on a station assembly flight Nov. 12.

But first up is Atlantis. The Hubble crew plans five back-to-back spacewalks to install the Wide Field Camera 3, the Cosmic Origins Spectrograph, a full set of batteries, six new stabilizing gyroscopes, a new fine guidance sensor, new insulation and carry out repairs on two other science instruments that are currently out of action. The upgrades and repairs are expected to extend Hubble's scientific life five to seven years.

Engineers had planned to haul the new gear to the launch pad early Friday for installation in the shuttle's cargo bay. The SLIC houses Hubble's new batteries, the Wide Field Camera 3 and other equipment. Another carrier, called the orbital replacement unit carrier, houses the new spectrograph, the fine guidance sensor, the new gyros and instrument repair equipment.

The cargo carriers are moved to the pad in a huge container that mirrors the shuttle's 60-foot by 15-foot payload bay. Once at the pad, the container will be lifted into a payload changeout room so the SLIC, the ORUC and other gear can be mounted in the cargo bay for launch.

"Right now, it's at least a 24-hour delay (on delivery) to the launch pad," Beutel said. "Senior managers are looking at what effect that might have on the target launch date of Oct. 10."

The delay initially appeared to ruin plans for a photo opportunity showing both shuttles on NASA's two launch pads with gantries rolled back out of the way. This is believed to be the last time in program history when two shuttles will be on the pad at the same time. With the Atlantis payload delivery delay, it appeared the protective gantries that shield both vehicles would not be rolled back at the same time. With Endeavour's rollout delay, however, the photo-op timing might still work out.

NASA sources said earlier today a launch delay appeared likely for Atlantis, but if no major contamination is found engineers may be able to make up the lost time and keep launch on track for 12:33 a.m. on Oct. 10.

A wild card in NASA's planning is recovery operations in Texas where Hurricane Ike devastated communities near the Johnson Space Center, located between Houston and Galveston. The space center escaped major damage, but nearby neighborhoods were not so lucky. NASA hopes to reopen Johnson Monday, but it's not yet clear what impact the hurricane might still have on the NASA-contractor workforce.

If launch slips to Oct. 11, readers are advised NASA has two possible launch times in the Eastern time zone: 12:03 a.m. and 11:36 p.m. The former would represent a 24-hour delay and the latter a 48-hour slip, even though both fall on Oct. 11. But again, no such delay has been announced and NASA managers are hopeful they can maintain the Oct. 10 target.


01:00 PM, 9/13/08: NASA assesses hurricane damage at Johnson Space Center

A rideout team at the Johnson Space Center endured a virtual direct hit from Hurricane Ike early Saturday, firing up generators to keep sensitive computer and communications gear in mission control on line when power was lost. A detailed assessment is not yet available, but officials said no injuries were reported and the space center appeared to escape major damage.

A team of flight controllers based at a hotel near Austin remained in contact with the international space station throughout the storm, using laptop computers and a high-speed NASA communications system. The mood was somber, insiders said, because like other Houston residents who left the area before Ike roared ashore, the controllers do not yet know whether their homes survived or how much damage they might face when they return.

In the meantime, U.S. and Russian flight controllers hope to press ahead with the delayed docking of an unmanned Russian supply ship Wednesday at 2:43 p.m. The cargo craft was launched from the Baikonur Cosmodrome in Kazakhstan last Wednesday and originally was scheduled to dock Friday.

But NASA's backup control center is not as capable as the main space center facility and at NASA's request, Russian controllers delayed the Progress docking and put the craft in a parking orbit. Depending on the reliability of the backup center's communications gear, U.S. space station control may be switched to NASA's Marshall Space Flight Center in Huntsville, Ala., for the Progress docking.

But NASA operations will be severely constrained until power is restored at Johnson. The generators currently powering mission control only have enough fuel for three to five days of around-the-clock operation and computer support needed by NASA personnel in Moscow is off line.

There is standing water on the grounds of the Johnson Space Center and rain intrusion through the roof of Building 30, where mission control is located, but the rideout team reported no major damage.

At nearby Ellington Field, where NASA bases its fleet of training jets, hangar damage was reported but most of the agency's planes were moved to El Paso before Ike came ashore.

There is no word yet on how long the space center will be closed or, more important, what impact Ike might have had on the homes of the NASA-contractor workforce. As such, it is too soon to say whether the storm will have any impact on NASA's plans to launch the shuttle Atlantis Oct. 10 on a mission to service and upgrade the Hubble Space Telescope.

NASA hopes to follow that mission by launching the shuttle Endeavour on a space station assembly mission Nov. 12. That flight must get off the ground by Nov. 25, or launch will slip into next year because of thermal issues related to the angle between the sun and the station's orbit.

Crew training and normal processing for both missions already were on a tight schedule. Given the apparent damage to the Clear Lake area around the Johnson Space Center, the launch schedule may be difficult to maintain.


11:45 AM, 9/11/08: JSC braces for Hurricane Ike; backup control center activated; STS-125 readiness review delayed (UPDATED at 6:14 PM with updated NHC track)

With Hurricane Ike bearing down on the coast of Texas, NASA managers today activated a rudimentary mission control center near Austin and ordered agency and contractor employees to evacuate the Johnson Space Center. A program-level flight readiness review for the next shuttle mission - a flight to service the Hubble Space Telescope - was delayed to next week.

As of this writing, it is not yet known what impact the hurricane might have on NASA's plans to launch the shuttle Atlantis on Oct. 10. Based on the 5 p.m. update from the National Hurricane Center, the center of the projected cone showing where Ike might ultimately go passes within about one mile of the Johnson Space Center.


5 p.m., 09/11/08 Update: National Hurricane Center projected track of Hurricane Ike passing the Johnson Space Center

A rideout team plans to be in place inside mission control throughout the storm. Critical computer and communications systems will remained powered up as long as possible and the team is prepared to safely shut them down if required. NASA training jets at nearby Ellington Field have been flown to El Paso, Texas.

Ike has already had an impact on space station operations. Early today, U.S. flight control switched from Johnson to a hotel near Austin, Texas. Using laptop computers with secure, high-speed internet connectivity, Johnson flight controllers, working around the clock in three shifts, are staying in contact with the space station and monitoring critical systems.

Another team of flight controllers will be stationed at the Marshall Space Flight Center in Huntsville, Ala., to take over if the Johnson Space Center loses power and the ability to relay communications to and from the backup center near Austin.

But some systems cannot be commanded from the backup control center, including precision control of solar array orientation. Such control is needed to "feather" the arrays before visiting spacecraft can dock to prevent contamination by rocket exhaust plumes. As a result, Russian space program officials may have to delay Friday's planned docking of an unmanned Progress supply ship launched from the Baikonur Cosmodrome on Wednesday.

At the Kennedy Space Center in Florida, meanwhile, engineers moved the space shuttle Endeavour from its processing hangar to the Vehicle Assembly Building early today for attachment to an external tank and boosters. If all goes well, Endeavour will be hauled to pad 39B before dawn on Sept. 18. It will be the first time since July 2001 that NASA has had two shuttles on its two launch pads at the same time.

The Hubble crew, launching from pad 39A, cannot seek safe haven aboard the international space station if a major problem prevents a safe re-entry. As a result, Endeavour is being prepped for a quick-response rescue mission if necessary. If no such mission is needed, Endeavour will be moved to pad 39A and prepped for launch Nov. 12 on a space station assesmbly flight.


12:18 PM, 9/5/08: Launch delayed two days to accommodate Hubble payload processing

As expected, NASA managers today decided to delay the shuttle Atlantis' launch on NASA's final Hubble Space Telescope servicing mission by two days, from Oct. 8 to Oct. 10 (at 12:33 a.m.), to give engineers more time to complete payload processing. Program managers also moved launch of the shuttle Endeavour on the next space station assembly mission from Nov. 10 to Nov. 12 ( at 8:43 p.m.).

Detailed flight plans for both missions, revised to reflect the new target launch dates, are posted on the CBS News STS-125 Quick-Look page. Flight planners are expected to adjust the launch time for Atlantis by several minutes based on lighting and ascent performance. In the meantime, here are mission highlights at a glance (in Eastern/mission elapsed time):

DATE/TIME......DD...HH...MM...EVENT

10/10/08
Fri 12:33 AM...00...00...00...STS-125 launch

10/11/08
Sat 11:47 PM...01...23...14...Hubble space Telescope capture

10/12/08
Sun 05:48 PM...02...17...15...EVA-1 begins (RSUs, batteries)

10/13/08
Mon 05:48 PM...03...17...15...EVA-2 begins (WFC-3, batteries)

10/14/08
Tue 05:48 PM...04...17...15...EVA-3 begins (COS, ACS repair 1)

10/15/08
Wed 05:48 PM...05...17...15...EVA-4 begins (STIS repair)

10/16/08
Thu 05:48 PM...06...17...15...EVA-5 begins (ACS repair 2, FGS)

10/17/08
Fri 07:31 PM...07...18...58...HST release

10/20/08
Mon 10:21 PM...10...21...48...Landing


6:30 PM, 9/4/08: Shuttle Atlantis hauled to launch pad

Bolted to a mobile launch platform atop a massive crawler-transporter, the shuttle Atlantis was slowly hauled from NASA's Vehicle Assembly Building to launch pad 39A today for work to ready the ship for blastoff around Oct. 8 on a final mission to service and upgrade the Hubble Space Telescope.

The 3.2-mile trip began at 9:19 a.m. and was completed at 3:52 p.m. when the MLP was "hard down" on support pedestal's at the seaside launch stand.

Launch currently is targeted for 1:34:52 a.m. on Oct. 8, but the flight is expected to slip two days or so because of time needed to complete Hubble payload processing. That processing was interrupted when the Kennedy Space Center was closed for tropical storm Fay and the team has been unable to make up the lost time.

Rollout to the pad was delayed a week because of Fay and because of technical problems with a propellant feedline connection. It was delayed another two days because of the threat of tropical storm Hanna.

That system is now expected to pass well to the east of the Florida peninsula, but NASA managers are keeping close tabs on the progress of Hurricane Ike in the mid Atlantic Ocean. It is not yet known whether Ike will pose any threat to the Kennedy Space Center next week, but NASA managers expect enough warning to move Atlantis back to the protection of the VAB if necessary.

Hubble Servicing Mission No. 4 is the only flight left on NASA's shuttle manifest that is not bound to the international space station. Because the space telescope is in a different orbit, Atlantis' crew cannot seek "safe haven" aboard the lab complex in case of a Columbia-class problem that might prevent a safe re-entry.

As a result, NASA Administrator Mike Griffin decided early on to process a second shuttle - Endeavour - in parallel to serve as a rescue vehicle. Engineers currently plan to haul Endeavour to launch pad 39B on Sept. 19. The Hubble crew plans to strap in aboard Atlantis five days later for a dress-rehearsal countdown that will set the stage for launch.

Assuming a rescue flight is not needed, Endeavour will be moved to pad 39A and prepared for launch on the next space station assembly mission around Nov. 10.


5:30 PM, 8/29/08: Shuttle rollout delayed by Hurricane Hanna

Already running four days late because of Tropical Storm Fay and another three because of a technical snag, the shuttle Atlantis' move to launch pad 39A was held up another 24 hours today, from Tuesday to at least Wednesday, because of uncertainty about the possible impact of Hurricane Hanna.

The National Hurricane Center predicts Hanna will pass relatively close to the Kennedy Space Center as it moves along a track 100 miles or so to the east overnight Thursday and Friday before slamming into the mainland near Savannah, Ga. The decision to delay rollout by 24 hours will give NASA managers another day to assess Hanna's track and it's potential impact on the space center.

Hurricane Gustav, meanwhile, roared ashore in Louisiana earlier today, passing to the southwest of New Orleans and Lockheed Martin's Michoud Assembly Facility where space shuttle external tanks are built. While company officials have not yet carried out a detailed inspection, NASA sources say the sprawling facility appears to have come through in relatively good shape.

As if dodging two hurricanes was not enough to worry about, NASA managers also are tracking the development of tropical storm Ike in the mid Atlantic Ocean. Ike is expected to strengthen to hurricane status and while it doesn't appear to threaten Florida's east coast, it's too soon to say where the storm might eventually go.

NASA hopes to launch Atlantis around Oct. 8 on the agency's fifth and final mission to service the Hubble Space Telescope. Even with the delays to date, shuttle workers still have several days of on-pad contingency time to handle unexpected problems.

But engineers preparing Hubble hardware for launch also fell behind because of Fay and unlike their shuttle colleagues, they do not have any on-pad contingency time left. As of late last week, the Hubble team was two to three days behind schedule, raising the prospect of a launch delay to Oct. 10 or 11, regardless of the rollout delay.

NASA plans to follow Atlantis' mission by launching the shuttle Endeavour around Nov. 10 on a space station assembly flight. But the agency only has two weeks to get Endeavour off the pad before the angle between the sun and the lab complex reaches a point that precludes shuttle visits because of temperature constraints.

In that case, Endeavour's launching likely would slip into early next year, triggering downstream delays for subsequent flights. As a result, NASA managers want to preserve Endeavour's Nov. 10 launch target if at all possible to ensure an adequate cushion to handle weather or unexpected technical problems.

Endeavour is being processed in parallel to serve as an emergency rescue vehicle in case Atlantis suffers any damage that might prevent a safe re-entry. Just how much cushion Endeavour ends up with depends in part on when Atlantis gets off the ground and when Endeavour is cleared of its launch-on-need obligations.

Regardless of the threat of subsequent delays, NASA managers plan to stick with the current flight sequence. There has been talk in recent days about a possible mission flip flop - delaying Atlantis to early next year to ensure Endeavour gets off in November - if the Hubble flight falls too far behind. But officials said today they plan to stay in order, launching Atlantis first, then Endeavour.


8:25 PM, 8/24/08: Shuttle Atlantis moved to VAB; engineers discuss sound heard during STS-126 tank rotation

Delayed by tropical storm Fay, the shuttle Atlantis was moved from its hangar to the Vehicle Assembly Building Saturday evening and attached to its external tank and solid-fuel boosters. After tests and checkout, the assembled "stack" will be hauled from the VAB to pad 39A in about a week. Launch on NASA's final mission to service the Hubble Space Telescope is targeted for Oct. 8.

Because Atlantis' crew cannot seek "safe haven" aboard the space station if a post-launch problem prevents a safe re-entry, the shuttle Endeavour is being processed in parallel to serve as a rescue vehicle if needed. Processing has been going relatively smoothly, but engineers are assessing an unusual sound heard when Endeavour's external tank was rotated from horizontal to vertical recently in the VAB.

After debriefing on-scene engineers and technicians, taking X-rays and reviewing the tank's manufacturing history, troubleshooters do not yet know whether there is any debris inside the tank, whether the noise heard could have been debris falling from a crane or other equipment near the tank in the VAB or the result of something unrelated. It may not be possible to definitively pin down what might have caused the noise.

Engineers currently are assessing the fuel flow environment inside the tank, the strength of various screens and other safety features to make sure nothing could get sucked into one of the shuttle's main engines if any debris is, in fact, present.

A NASA spokesman said Sunday the issue remains open but so far, nothing has been found.


02:20 PM, 8/14/08: NASA sticks with Oct. 8 launch date for STS-125

NASA managers today decided to stick with Oct. 8 as the target launch date for shuttle mission STS-125, a long-awaited flight by the shuttle Atlantis to service and upgrade the Hubble Space Telescope. They also agreed to stick with Nov. 10 for launch of the flight after that, a space station assembly mission by the shuttle Endeavour.

As it now stands, Atlantis will be hauled to launch pad 39A on Aug. 26. Commander Scott Altman and his six crewmates - pilot Gregory C. Johnson, robot arm operator Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good - plan to strap in for a dress-rehearsal countdown on Sept. 19.

If all goes well, Atlantis will blast off around 1:34:49 a.m. on Oct. 8. After grappling the space telescope, the first of five back-to-back spacewalks will begin around 6:50 p.m. on Oct. 10 to install two new instruments, an upgraded fine guidance sensor, a new set of batteries and full set of gyroscopes. The astronauts also will attempt to repair two instruments that malfunctioned earlier and install fresh insulation. The flight plan calls for the astronauts to release the refurbished telescope on Oct. 15 and to land back at the Kennedy Space Center around 10:30 p.m. on Oct. 18.

STS-125 had been targeted for launch Aug. 28, but in May the flight was delayed because of time needed to ready two external fuel tanks. The Hubble repair crew cannot seek "safe haven" aboard the international space station if a Columbia-class heat-shield problem occurs. As a result, NASA Administrator Mike Griffin decided early on to have a second shuttle - Endeavour - prepped for launch on a rescue mission if necessary. Assuming no rescue flight is needed, Endeavour then would be used for the next station assembly mission, STS-126.

The Hubble rescue requirement meant two tanks had to be ready at roughly the same time and building new tanks with post-Columbia safety upgrades took a bit longer than initially expected. The Hubble launch slipped to Oct. 8 and Endeavour's flight was delayed from mid October to Nov. 10. A flight that had been planned for December slipped to February.

As it turned out, work to ready the next two tanks went smoothly and NASA managers recently asked engineers to look into the possibility of moving the next two flights up a few days, to Oct. 2 and Nov. 4 respectively. That later was amended to Oct. 5 and Nov. 7. Today, program managers agreed to stick with Oct. 8 and Nov. 10.

"It was a combination of things," a NASA spokesman said. "When they put that CR (launch date change request) out, they put it out with the understanding that tank processing needed to mature. They had to watch that for a while. That ended up turning out better than they hoped. The problem came with Hubble payload deliveries. Even if they hit every milestone they could possibly hit... the best they could do was Oct. 7."

The problem for Endeavour's flight was crew training. A tropical storm recently forced NASA to shut down the Johnson Space Center and Endeavour's crew lost valuable training time that could not be made up without violating work load guidelines. And so, the shuttle program decided to stick with the original Oct. 8 and Nov. 10 launch targets.

A detailed flight plan for STS-125 is posted on the CBS News STS-125 Quick-Look page, along with a launch windows chart, crew and personnel data.


4:30 PM, 7/25/08: NASA modifies launch date 'change request' to move up next two shuttle launchings

Space shuttle program managers today modified an official "change request" that, if approved, will move up the next two shuttle launchings by three days each, not six as initially requested.

As originally written, the CR would have moved launch of STS-125, a long-awaited mission to service the Hubble Space Telescope, from Oct. 8 to Oct. 2. The flight after that, STS-126, would have moved from Nov. 10 to Nov. 4 - election day in the United States.

But crew training, payload processing and work to ready external tanks for flight prompted managers today to request Oct. 5 for launch of the Hubble servicing mission and Nov. 7 for the subsequent space station assembly flight. A decision on whether to actually approve those target dates is expected Aug. 14.

Assuming the revised target dates are selected, the shuttle Atlantis would take off on the Hubble servicing mission at 3:02:18 a.m. EDT on Oct. 5. The telescope would be grappled around 1:28 a.m. on Oct. 7 and the first of five back-to-back spacewalks to service and upgrade the observatory would begin later that day at 8:17 p.m. If all goes well, Hubble would be released from the shuttle around 9:13 p.m. on Oct. 12 and Atlantis would land back at the Kennedy Space Center on Oct. 16 at 12:04 a.m.

Launch of shuttle Endeavour on mission STS-126 would occur around 10:39 p.m. on Nov. 7 followed by docking with the international space station around 8:11 p.m. on Nov. 9. Four spacewalks are planned - Nov. 11, 13, 15 and 17 - each one beginning around 4:29 p.m. Landing back at the Florida spaceport would be targeted for around 5:02 p.m. on Nov. 22.

Detailed flight plans will be posted after official launch targets are determined Aug. 14.


6:45 PM, 7/7/08: NASA unveils revised shuttle manifest; Shannon optimistic about completing program on time

NASA today unveiled a revised manifest for the final 10 flights in the space shuttle program, reflecting previously forecast delays across the board because of post-Columbia external tank safety upgrades that have stretched out deliveries. But shuttle Program Manager John Shannon said he's confident NASA can complete the space station and retire the shuttle fleet in 2010 as planned.

"There are challenges with that, that's really a no-contingency-days, no-big-problems kind of schedule," he told CBS News in a telephone interview. Even so, he added, "I think we have a very credible plan to get done, with some margin at the end of it."

Two more shuttle flights are planned this year, in October and November, five in 2009 and a final three missions in the first half of 2010 to bring the program to a close.

NASA had planned to retire the shuttle Atlantis after a final Hubble Space Telescope servicing mission in October, but the orbiter will make two more flights beyond that, one in 2009 and another in 2010, to provide additional processing margin. Atlantis and Discovery will fly three more times each and the shuttle Endeavour will make four more flights, including the 10th and final mission.

"The original rationale (for retiring Atlantis) was that we would take Atlantis down, it would save some money for the program and we would use it as a spares option for us," Shannon said. "We looked at our spares posture, and it was pretty good, it did not look like there was any pressing need to retire Atlantis.

"From a money standpoint, we were able to continue flying and continue processing Atlantis at no additional cost to the program and that is because we were ramping down all of our return-to-flight efforts and we had gotten more efficient in ground ops processing. So it did not cost us any additional money and on the positive side, it gives us a tremendous amount of manifest flexibility. It makes it much more feasible to finish the program on time."

Unlike Endeavour and Discovery, Atlantis is not equipped with a space station-to-shuttle power transfer system to tap into the station's solar power grid. But Shannon said the two station flights planned for Atlantis do not require the additional docked time the power transfer system provides and "it made a lot of sense to keep Atlantis flying."

Here is the revised manifest (a more detailed manifest is available here: http://cbsnews.cbs.com/network/news/space/manifest.html):

During a May 1 briefing to preview the just-completed flight of the shuttle Discovery, Shannon announced that STS-125, the Hubble servicing mission, would slip from August to October and the subsequent flight, STS-126, would slip from October to November. He said STS-119, which had been scheduled for launch in December, would move into 2009, all because of external tank processing issues. At that time, no other target dates were revealed pending additional assessment of tank delivery schedules.

The tank used by Discovery for the most recent shuttle launch on May 31 was the first to be built from scratch with post-Columbia safety upgrades and it took engineers at Lockheed Martin's Michoud Assembly Facility in New Orleans additional time to perfect and implement required manufacturing techniques.

Those issues were compounded for the upcoming launch of Atlantis on NASA's final planned Hubble Space Telescope servicing mission. Shuttle crews bound for the international space station have the option of "safe haven" aboard the lab complex, where they can await rescue by another shuttle if any Columbia-class problems occur that might prevent a safe re-entry. That is not possible for the Hubble repair crew because the telescope is in a different orbit and the shuttle cannot reach the station from there.

As a result, NASA plans to have a second shuttle ready for launch on short notice in case of any major problems and that, in turn, means two tanks will be needed.

In May, Shannon said the changes to the way external tanks are built "added about four to five weeks of processing time on those two tanks. The tank team has done a really nice job of taking the lessons learned processing the tank that's about to fly, and the Hubble tank. So I don't expect that to (expand the time needed) on each of the downstream tanks. They have a mitigation plan in place so that the 2009 tanks come in more on a normal template. So we're going to take a one-time hit of this four to five weeks, it will move pretty much all of the tanks in series, the next 10 tanks that will come out, about that four to five weeks."

Even so, Shannon said today that starting with STS-127 next May, the external tank team at Michoud will need to shave about a month off the time needed to manufacture each tank to keep the program on track.

"The schedule we've put together challenges the Michoud Assembly Facility production on the external tanks by about a month per tank," he said. "We partnered with them very closely to try and understand what production efficiencies we're going to have as we go through the next several builds of tanks. And we think we'll be able to get a month back. But that's not proven yet."

To provide as much margin as possible to cope with unexpected problems, the shuttle program wants to keep the shuttle Endeavour on track across its four upcoming flights. As it now stands, the final flight is targeted for launch on May 31.

NASA managers may opt to move up the next two flights by a few days, in part to provide additional margin for Endeavour. Based on ground processing alone, the Hubble mission likely could be moved up five to six days, Shannon said. But because of payload issues and crew training "they might get two or three days, it doesn't look like much more than that."

But that likely would enable NASA to launch Endeavour on mission STS-126 a few days ahead of the current Nov. 10 target. That's important because it would provide a few additional days of margin to get Endeavour off before a so-called beta angle cutout begins around Nov. 25. If the shuttle isn't off the ground by then, thermal issues caused by the angle between the sun and the plane of the station's orbit would prompt a significant launch delay.

"The beta ends in the middle of December, but we wouldn't launch then because of workforce issues, it would probably be the middle of January or early February," Shannon said. "Right there, you lose two months, almost three months off your critical path and we'd have to really struggle to make that up."

As a result, "we would really like to get 126 off before the beta cutout," Shannon said. "If we move Hubble up a few days, that would make us think we could move 126 up a few days and get a few more days before that beta angle constraint. That's really important to us because we want to keep on the timeline for the (Endeavour) flights."

As with all post-Columbia missions, NASA will have a set of boosters and an external tank available to support an emergency "launch on need" rescue mission for Endeavour's final flight. Congress is considering a plan to use that hardware for one additional flight, a mission to carry a high-tech physics experiment to the space station.

In the wake of the Columbia disaster and the 2010 deadline for completing shuttle operations, the Alpha Magnetic Spectrometer, or AMS, payload lost its ride to the station. Congressional supporters are considering whether to add a flight and Shannon said the agency was protecting that option.

"Right now, we don't have any direction to go fly the AMS from Congress or the White House," he said. "We've protected the option. We've put together a cargo layout that would have the AMS flying, we have had people from the shuttle program involved in integration to determine the long-lead integration items that we need in order to put it in the shuttle payload bay and be able to go fly it. And I am going to have, at the end of the program, hardware available to not only fly an additional flight but I would also have launch-on-need capability for that flight."

He said external tank 122, which was damaged in Hurricane Katrina, could be upgraded and prepared for launch-on-need use if needed. A set of boosters would have to be procured, but "I don't have to make the decision for configuring ET-122 or the extra boosters until the middle of next year," Shannon said. "So we'll wait and see what everybody wants to do."


4:15 PM, 6/26/08: Launch pad repair plan approved; no impact on Hubble servicing mission launch

Shuttle program managers today approved a plan to strip away fire bricks from damaged sections of the "flame trench" at launch pad 39A, to erect a steel grid over the exposed concrete back wall and to spray on a thick coating of heat-resistant Fondu Fyre to protect the structure from super-hot shuttle booster exhaust. The work, expected to cost less than $2.7 million, should be complete before the shuttle Atlantis is hauled to the pad at the end of August for blastoff Oct. 8 on a high-profile mission to service the Hubble Space Telescope.

"We really like the plan ... and we approved it," said shuttle Program Manager John Shannon. "We expect to start moving out on it right away."

During the shuttle Discovery's May 31 launch on a space station assembly mission, more than 3,500 fire bricks lining the northeast wall of the booster side of the flame trench at pad 39A were blasted away. Radar tracking showed some of the bricks exiting the trench at some 1,000 feet per second, or about 680 mph.

A detailed inspection found that many of the anchor plates used to secure the interlocking fire bricks to the 3-foot-thick concrete back wall were heavily eroded due to decades of exposure to severe pressures and acidic rocket exhaust. In addition, epoxy used to help secure the bricks to the wall was degraded or not consistently applied when the pad was built in the mid 1960s. As a result, the outer brick wall was not tightly locked to the underlying concrete wall it was designed to protect.

"We did find evidence of a fracture joint along a construction joint between the first and second panels of the east wall," said Perry Becker, chief of NASA's structural systems branch at the Kennedy Space Center. "We believe that fracture was brought on by a number of different components. We have found erosion of some anchor plates that were used to secure the brick to the back wall. We've found degradation of the epoxy that was used to adhere the brick to the back wall. We have found evidence of acid deposition in that area. We've found evidence of carbonation in the area, which leeches the calcium out of the concrete, which reduces the strength of the mortar-to-concrete joints."

Becker said the damage that occurred during Discovery's May 31 liftoff apparently happened when a Fondu Fyre patch over an area of earlier erosion ripped away seconds after booster ignition.

"We believe, based on pre- and post-launch pictures, that we liberated a Fondu Fyre patch that was put over an area of fairly significant erosion," he said. "We think the lack of adhesion on that wall resulted in some bowing off the back wall and resulted in the liberation of that patch. Once that patch was liberated at launch, we believe that created the intrusion point that got the hot gas behind the wall."

Once booster exhaust gases got behind the brick layer, "we had impingement on the back wall and with no real adhesive strength left in that local area, we started a localized failure," Becker said. "Due to the interlocking nature of the brick, we believe that led to a cascading failure on down the wall."

To fix the trench, bricks covering a 25-by-100-foot section of the east wall of the trench, along with a 25-by-80-foot section of the west wall, will be removed. A steel mesh-like structure will be erected over the exposed backwall and then covered in sprayed-on Fondu Fyre, a material already used to protect the massive flame deflector directly under the shuttle's boosters and main engines.

Working two 10-hour shifts per day, the repair team expects to have the brick removed by July 19. After that, the mesh will be erected and the Fondue Fyre applied. Space shuttle processing manager Rita Willcoxon said the repair should be complete by the third week in August. The shuttle Atlantis is scheduled to be hauled to the pad Aug. 29.

Becker said the repaired flame trench will be closely inspected after every launch, but he expects it to hold up through the end of shuttle operations in 2010.

Nearby pad 39B is believed to have similar weaknesses in its flame trench. But no major repairs are envisioned in the near term. All 10 remaining shuttle flights are scheduled to use pad 39A and while NASA could use pad 39B for a rescue mission should Atlantis suffer major damage during the Hubble flight, a detailed analysis shows no debris from either pad's flame trench could reach a shuttle or cause any damage.

"We also discussed in a lot of detail the transport analysis to see if there was any risk to the space shuttle vehicle from anything liberated from the trench," Shannon said. "We got good results that said that would not be any kind of a risk to the vehicle."

Pad 39B currently is being modified for use by the new Ares 1 rockets that will carry the Orion crew capsules intended to replace the shuttle. A longer-term fix for the flame trench may be required down the road, but no final decisions have been made.


5:35 PM, 6/16/08: Pad repair likely will involve brick removal, application of spray-on Fondu Fyre

Engineers assessing extensive damage to launch pad 39A during the shuttle Discovery's May 31 takeoff said today they are confident the "flame trench" that diverts exhaust to either side can be repaired in time for NASA's next mission, the Oct. 8 launch of shuttle Atlantis on a flight to service the Hubble Space Telescope.

Repair options will be presented to shuttle Program Manager John Shannon on June 26, leaving about two months to complete the pad rehab before the planned Aug. 29 rollout of Atlantis.

"We feel we're on the right path for a design solution and we're working to get there," Perry Becker, chief of NASA's structural systems branch at the Kennedy Space Center, told reporters today. "We're working very extensively with a few vendors in industry, we're starting to put that plan together. ... We're confident, regardless of the scope of the work here, that we can repair this pad in time and support the rollout."

During Discovery's takeoff, some 5,300 heat-resistant bricks lining the northeast wall of the flame trench under the shuttle's mobile launch platform were blown away, some blasted more than 1,800 feet, heavily damaging a security fence around the pad perimeter. The interlocking bricks, held in place by epoxy and metal clips anchored in concrete, are used to protect an underlying 3-foot-thick concrete wall that helps form the structural backbone of the pad.

The missing bricks exposed an irregular area of the concrete wall measuring roughly 20 feet by 75 feet. New bricks cannot be manufactured in time to support the Hubble mission, but Becker said engineers believe the trench can be repaired by stripping away additional bricks around the damage area, erecting a steel mesh framework and then spraying on a thick coating of a refractory material like Fondu Fyre.

A five-inch-thick coating of Fondu Fyre currently covers the inverted V-shaped flame deflector that diverts main engine exhaust to one side of the pad and booster exhaust to the other. About 20 feet of the flame trench extending from the deflector on the booster side already is covered by Fondu Fyre, giving way to bricks. The idea would be to extend that coating to cover the areas damaged during Discovery's launching.

"We're certainly looking strongly at Fondu Fyre, we've got a history with it out here, we know its properties," Becker said. "There are a couple of other materials on the market that we're looking at, so we haven't down selected that definitively. But it is a leading candidate."

Despite the intense heat and pressure produced by the shuttle's solid-fuel boosters, Becker said the Fondu Fyre coating the flame deflector holds up well to the extreme heat and pressures produced by the shuttle's huge solid-fuel boosters.

"The erosion rate we would expect on the side walls (of the flame trench) would be very, very minimal based on some Fondu Fyre that we have up near the main flame deflector itself," he said. "That has performed very well."

It is not yet known how many more bricks will need to be stripped away or how large an area might ultimately be covered by Fondu Fyre, assuming program managers approve that approach.

"I like to talk about it as if you're redoing tile in your bathroom at your house," said Ed Mango, launch director for the Hubble servicing mission. "One tile gets loose, then you've got to chase it. This is a similar thing. The tile in your shower is there to protect the wall behind it. We have the brick here to protect the concrete behind it. Of course, the over pressure and the amount of water is much worse!"

Looking at trowel marks on the exposed concrete, engineers believe the epoxy used to help hold the bricks to the wall was not uniformly applied. So-called "tap tests" have revealed possible voids behind other sections of the flame trench where bricks are still in place.

"We have seen indications on the visibly damaged sections of trowel marks in some areas on the wall there that shows less than full engagement of the bricks to the back wall structure when it was originally manufactured," Becker said. "Certainly, that is one component of several possibilities of the root cause of failure."

Becker downplayed the question of whether the original construction was flawed, saying "there's no such thing as a perfectly vertical or smooth wall. So there are going to be voids and surface imperfections, that's common in the construction industry."

The Hubble crew cannot take advantage of "safe haven" aboard the international space station if Atlantis suffers any damage that might prevent a safe re-entry. As a result, NASA plans to have a second shuttle, Endeavour, ready for takeoff from nearby pad 39B if a rescue mission is required.

Both shuttle pads were built in the 1960s for the Apollo moon program and engineers are carrying out tests and inspections to assess the health of pad B.

"We're evaluating that state of pad B as we speak and if we find anything, we'll take the appropriate action," Becker said.

First used in 1967, pad 39A has withstood 12 Saturn 5 launchings, including the first Apollo moon landing mission, and 70 shuttle flights. Pad 39B, first used in 1969, supported one Saturn 5 launch, four Saturn 1B flights and 53 shuttle missions, including Challenger's final flight.