STS-85 MISSION ARCHIVE (complete) Updated: 08/19/97 CRISTA-SPAS By William Harwood CBS News/Kennedy Space Center The following copy originally was posted on the CBS News "Up To The Minute" Current Mission space page (http://uttm.com/space/missions/current.html). Comments and corrections welcome! TABLE OF CONTENTS -Shuttle Discovery returns to Earth (08/19/97) -Shuttle entry delayed by prospect of fog (08/18/97) -Astronauts complete mission objectives, gear up for landing (08/17/97) -Astronauts retrieve atmospheric research satellite (08/16/97) -Astronauts wrap up orbital research (08/15/97) -Additional arm tests planned (08/14/97) -Computer problems interrupt robot arm tests (08/13/97) -Astronauts study Hale-Bopp comet (08/12/97) -Robot arm put through paces (filed 08/11/97) -Shuttle satellite may confirm comet theory (filed 08/10/97) -Shuttle satellite sniffs out volcano; crew studies comet (08/09/97) -Engineers track down communications glitch (filed 08/08/97) -Shuttle Discovery rockets into orbit (08/07/97) -Shuttle countdown update (08/06/97) -Shuttle countdown update (08/05/97) =================================================================== Shuttle Discovery returns to Earth (08/19/97) The Discovery astronauts plunged back to Earth today, gliding to a smooth dawn touchdown in Florida to close out a successful 11-day science and technology development mission. Among their other accomplishments, the astronauts brought back a reusable German science satellite loaded with data about the destruction of Earth's protective ozone layer. "It's a pleasure to be back here at KSC," commander Curt Brown said after touchdown. "There's kind of the good news and the bad news. We are really glad to be back to Earth and back with our families and loved ones. The bad news is we're kind of ashamed we can't stay up in space in our home and do some more work. Hopefully, we'll have a chance to go do that again real soon." Flying upside down and backward above the southern Indian Ocean west of Australia, Brown and pilot Kent Rominger fired Discovery's twin braking rockets at 6:08 a.m. for two minutes and 14 seconds, slowing the shuttle by 230 feet per second to drop out of orbit. The spaceplane fell into the discernible atmosphere 378,000 feet above the South Pacific Ocean and approached Florida from the southwest, on the ascending node of orbit 190. Discovery's ground track crossed the Yucatan Peninsula and passed just west of Cuba before crossing the Florida coastline south of Tampa. After a sweeping right overhead turn to line up on runway 33, Brown guided Discovery to a picture perfect touchdown at 7:07:59 a.m. after 189 complete orbits spanning 4.7 million miles since blastoff Aug. 7. Mission duration was 11 days 20 hours 26 minutes and 59 seconds. "Wheels stopped, Houston," Brown radioed Houston as the shuttle rolled to a halt. "Copy wheels stopped, Discovery; welcome home, it looked like a perfect flight from start to finish," called astronaut Dom Gorie from mission control. "And Discovery's glad to be home," Brown replied. Shuttle program manager Tommy Holloway said the flight "went extremely well," adding his "congratulations to the entire team." Landing originally was scheduled for Monday, but entry flight director Wayne Hale ultimately ordered the crew to stay in orbit an extra day because of concern about the possible development of ground-obscuring fog between the deorbit rocket firing and touchdown. As it turned out, conditions were near ideal, but hindsight is always 20-20 and given the conditions at the time, Hale made the properly conservative decision. "When you have no difference between the air temperature and the dew point temperature and light winds, there is always a strong possibility (fog can develop)," Hale said today. "So based on that possibility ... we decided we had plenty of consumables on board, there was no reason to be in a hurry, there was no reason to take any chances and the prudent thing to do was wait for another day." Today's touchdown marked the 39th shuttle landing at the Cape in program history, the 76th day landing overall and the 10th consecutive return to Florida. Seventeen of the last 18 shuttle missions have ended at KSC. "It was a beautiful morning to land in Florida," Hale said. "Everything went by the numbers, we had no problems on board the orbiter, the crew executed flawlessly, commander Curt Brown in his first command, flew it right down the pike and it looked like a perfect landing from all the data I've seen." With their flight now behind them, Brown, Rominger, flight engineer Robert Curbeam, Jan Davis, Stephen Robinson and Canadian astronaut Bjarni Tryggvason planned to fly back to the Johnson Space Center later today for reunions with friends and family members. "Discovery's in great shape," Brown said. "And all the folks here at Kennedy Space Center should be very, very proud of all the work they've done because Discovery had absolutely zero problems during our 12-day flight. So we sure do appreciate that." The astronauts accomplished the primary goal of the 86th shuttle flight Saturday when Davis, operating Discovery's 50 foot-long robot arm, plucked the CRISTA-SPAS atmospheric research satellite out of open space for return to Earth. The reusable German satellite was launched seven-and-a-half hours after Discovery's takeoff for nine days of independent operation. Making its second flight with the same two instrument packages, CRISTA-SPAS spent some 200 hours measuring trace gases that affect ozone depletion to learn more about the chemistry and global transport of such materials. The long-range goal is to improve computer models that predict the atmosphere's response to varying levels of pollutants. Most of the data was stored on board the satellite and it will take scientists months to complete their analysis. But preliminary data from a Naval Research Laboratory instrument shows higher-than-expected levels of hydroxyl molecules in the upper atmosphere at high northern latitudes, indicating high levels of water vapor. Current theory cannot explain these levels of water vapor and the CRISTA-SPAS data may lend more credence to a controversial theory by University of Iowa space scientist Lou Frank that Earth is constantly being bombarded with small house-size comets. While the CRISTA-SPAS satellite was operating on its own, Discovery's crew put a prototype Japanese-built robot arm through its paces that will be used aboard the international space station to move items about and perform routine maintenance that might otherwise require a spacewalking astronaut. The arm is intended to be used with the Japanese Experiment Module and can be operated from the ground in the absence of crew members. Two major suites of experiments were mounted in Discovery's cargo bay and operated by ground controllers, including an instrument to measure solar radiation, others to study ultraviolet light from astronomical targets and still others to probe Earth's atmosphere in concert with CRISTA-SPAS. Mission managers said the astronauts accomplished virtually all of their primary objectives with only a handful of relatively minor snags. "Maybe it's not a showy mission like the Mir docking missions or an EVA mission, but it's an example of the kind of things we have to do to get ready to build space station," said entry flight director Wayne Hale. "It's really hauled the freight in terms of the scientific experiments. We've learned more about Earth's ozone layer, we've demonstrated new capabilities with the new robot arm that we're going to put on the space station, we've learned new techniques for how to assemble the space station with the Space Vision System and some other experiments. We have a number of payloads and they are all operating and we're going to get all the objectives we set out to get." =================================================================== Shuttle entry delayed by prospect of fog (08/18/97) The Discovery astronauts were ordered to delay landing 24 hours, from Monday to Tuesday at 7:07:41 a.m., because of concern about possible fog near the shuttle runway this morning. Flight director Wayne Hale at the Johnson Space Center in Houston made the decision at 6:01 a.m., just 13 minutes before Discovery commander Curt Brown was to fire Discovery's twin braking rockets to drop out of orbit for a planned 7:13:59 a.m. landing at the Kennedy Space Center. "Discovery, Houston. At this time we're going to call off the deorbit burn attempt," called astronaut Dom Gorie in mission control. "The probability of fog is too high to be acceptable. So on page three-dash-11 and 12, we'd like to work the ... no-go for deorbit burn and 24-hour extension." "OK, Dom, I copy," Brown replied. As it turned out, fog never developed and conditions appeared near ideal at landing time. But it takes a full hour for a shuttle to fall back to Earth after deorbit ignition and once the trip begins, the crew is committed. Hindsight is always 20-20, but given the conditions at the time, Hale and his team made the properly conservative call. The decision to terminate re-entry procedures came about seven hours into the crew's day. Brown and company promptly reopened the shuttle's cargo bay doors, but Gorie told them not to redeploy their KU-band television antenna. Virtually all of the shuttle's science objectives already have been met and no additional work of any significance is planned. But the astronauts were given permission to reactivate two suites of cargo bay experiments, IEH and TAS-01, which will be operated by the ground, and another experiment called TP-FLEX. The crew will go to bed around 3 p.m. Discovery has two landing opportunities Tuesday but the first, which would require a deorbit rocket firing at 4:38 a.m. for a touchdown at 5:35 a.m. - one hour and 18 minutes before sunrise - has been ruled out. The second opportunity, the one preferred by NASA, begins with a deorbit burn at 6:08 a.m. and a touchdown at 7:07:41 a.m., 13 minutes after sunrise. Here's the preliminary timeline for a daylight landing: TIME............EVENT 02:08:00 a.m....The crew switches to the deorbit timeline 03:28:00 a.m....Discovery's cargo bay doors are closed 03:50:00 a.m....The orbiter's flight computers switch to OPS-3 software 04:14:00 a.m....The crew reviews entry procedures 04:43:00 a.m....The astronauts begin donning their pressure suits 05:47:00 a.m....Mission control gives a formal "go" for re-entry 06:08:00 a.m....Deorbit ignition 06:35:45 a.m....The shuttle enters the atmosphere 5,173 miles from Florida 07:07:41 a.m....Landing on runway 33 at the Kennedy Space Center While a daylight landing is always preferred, NASA's mission management team briefly considered the possibility of bringing the entry team of flight controllers in a bit early this evening to protect the possibility of bringing the astronauts home in darkness if the prospect of dawn fog crops up again. But managers quickly ruled out that possibility and decided to stick with the original plans for a daylight landing. NASA will not, however, activate the shuttle landing team at Edwards Air Force Base, Calif. Discovery has enough on-board supplies to remain in orbit until Thursday and Edwards will not be activated until Wednesday. At that point, the shuttle would land on one coast or the other. =================================================================== Astronauts complete mission objectives, gear up for landing (08/17/97) Aboard Discovery today, the astronauts carried out a flight control system checkout and test fired the orbiter's small steering jets to make sure they will be ready for use Monday morning. Later, commander Curt Brown and pilot Kent Rominger lowered Discovery's orbit to 159 nautical miles to facilitate atmospheric observations by instruments in the shuttle's cargo bay. In addition, the crew used the shuttle's robot arm to pick up the CRISTA-SPAS atmospheric research satellite, moving it about to test a Canadian-built Space Vision System. The SVS gives arm operators very precise information about the arm's position and the system is expected to be used during space station assembly and maintenance. Other experiments mounted in Discovery's cargo bay are still in operation, remotely controlled from the ground. "We've been having a very successful mission," entry flight director Wayne Hale recapped. "We retrieved the SPAS satellite yesterday, put it away for the night, got it back out again this morning to run a number of tests with the Space Vision System, which is an engineering piece of gear we hope to use aboard the international space station during its assembly and use. We've had a full compliment of science activities today interspersed between our preparations for the deorbit and landing tomorrow. We did a flight control system checkout that was completely successful, we had no anomalies at all. Everything checked out perfectly, Discovery's in great shape, the crew is in excellent spirits." Hale said the 86th shuttle mission was "very challenging ... from the aspect of science." "Maybe it's not a showy mission like the Mir docking missions or an EVA mission, but it's an example of the kind of things we have to do to get ready to build space station," he said. "It's really hauled the freight in terms of the scientific experiments. We've learned more about Earth's ozone layer, we've demonstrated new capabilities with the new robot arm that we're going to put on the space station, we've learned new techniques for how to assemble the space station with the Space Vision System and some other experiments. We have a number of payloads and they are all operating and we're going to get all the objectives we set out to get." =================================================================== Astronauts retrieve atmospheric research satellite (08/16/97) The Discovery astronauts chased down the CRISTA-SPAS atmospheric resarch satellite today and used the shuttle's robot arm to pluck it out of open space for return to Earth. Astronaut Jan Davis, operating the Canadian-built space crane, captured the satellite at 11:14 a.m. as the two spacecraft sailed high above New Zealand. "Houston, Discovery, we show a good grapple," Davis radioed after the arm locked onto the satellite. "Great job, Discovery. Congratulations on a very smooth rendezvous and grapple," replied astronaut Ellen Ochoa from mission control. Today's rendezvous went smoothly with no apparent problems, ending nine days of free flight for the reusabler German satellite. Commander Curt Brown and pilot Kent Rominger used the opportunity to test a new space station rendezvous technique. Here's how Brown described the rendezvous procedure in a pre-launch NASA interview: Normally we just come in on an R-bar approach, which should be approaching the payload from underneath, from the Earth's side of the payload, and basically flying up a line, that if you do a line from the payload to the Earth, flying up that line to within range to grab the payload and then we'd grab it. On STS-85, we're doing a TORFA, which is a Twice Orbital Rate Fly Around approach, where we come up on the R-bar, just like a normal rendezvous, until about the 500 foot point, at that point, we'll start a fly-around. And we'll fly around from that R-bar up to the V-bar, 90¡ of angle change. And once we get to the V-bar, we'll stop there, and then fly in on the V-bar from about 250 feet on into grapple range. That is what we do on our normal space station rendezvous. We have corridor requirements, and we have closure requirements that we must meet. We'll fly into about 30 feet. We'll station-keep at 30 feet for a few moments simulating station-keeping that we do on a space station, and then we'll start a closure rate, a very specific closure rate, from that 30 feet on into simulated docking. And then at that point, we'll knock off the test, and we'll back back out to the indefector range and grapple the CRISTA-SPAS with the arm. There are a lot more details to the rendezvous other than that, but that's pretty much a big picture of it. We'll be doing some jet testing using different number of reaction control jets to do our maneuvers, again for plume requirements and plume data on the International Space Station assembly. Depending on the configuration of the International Space Station, they have to do different approaches. And this will be used during some of that assembly, assuming the DTO goes as the engineers expect it to go, which we have no doubt it will. =================================================================== Astronauts wrap up orbital research (08/15/97) The Discovery astronauts made final observations of comet Hale-Bopp today and stood by while ground controllers remotely operated a Japanese robotic arm before stowing the space crane for return to Earth. During a news conference, commander Curt Brown said the 86th shuttle mission had accomplished virtually all of its major objectives, setting the stage for rendezvous and retrieval Saturday of the CRISTA-SPAS atmospheric research satellite launched Aug. 7. "The mission has been going great," he said. "We've completed eight days of very intense payload operations and all those have gone very smoothly. We've had a few things to slow us down, we've gotten behind in the timeline a little bit, but due to the extraordinary efforts of the folks on the ground, we were able to blend those back into the next day's activities so we're right where we should be. With all the activities we have, it's going to be one of the shuttle missions we can look back on and be very, very proud of." If all goes well, Discovery will glide to a landing at the Kennedy Space Center around 7:05 a.m. Monday to close out an 11-day flight. In other space news, Mir-24 commander Anatoly Solovyev, flight enginer Pavel Vinogradov and and U.S. astronaut Michael Foale strapped into their Soyuz TM-26 transport vehicle today and undocked from the crippled Mir space station's Kvant-1 docking port. Stationkeeping about 150 feet away, the crew members stood by while flight controllers sent commands to rotate the space station 180 degrees. After videotaping the damaged Spektr module, the cosmonauts redocked with MIr's access node, the same port that was vacated Thursday when the hard-luck Mir-23 crew returned to Earth. By moving Soyuz TM-26 to the access node port, the Mir-24 crew freed up the Kvant-1 port for the redocking of a Progress resupply vehicle that was undocked and parked nearby earlier this month to make way for the Mir-24 crew's arrival Aug. 7. Videotape from today's inspection is not expected to be downlinked from Mir until early next week. Will advise. Back aboad Discovery, the astronauts and ground controllers completed tests on the Japanese Manipulator Flight Demonstration unit, a 1.5-meter prototype robot arm intended for use on the international space station. A major goal was to operate the arm remotely from the ground, which will be necessary from time to time during station operations. Problems with the computer network on the shuttle that routes software and commands to the arm itself prevented such tests Wednesday, but today's operations went fairly smoothly and the arm was stowed for entry shortly after 8 a.m. "That went very well most of today, we only missed one right at the end when we lost the computer lock," said payload commander Jan Davis. "So we proved the ground commanding works and I think that was really a real triumph to command the arm from the ground and that really proves we'll be ready for the international space station. The few little glitches we've had, I think, really proved that the system works well and the surprises we have had are understood and we certainly can work on those." Overall, she said, "I'd give it an A plus. It's really been fun for Steve (Robinson) and I to fly the arm through all the different scenarios we have and it's performed very well. There are some things we really could not even test on the ground, some of the compliance functions, and we sort of feel like test pilots up here trying out the arm. We have taken it to the edge of its envelope and tested every possible mode and I think we have a lot of good data. We're still learning a lot about it and we'll be ready for international space station." While the robot arm and the CRISTA-SPAS satellite have garnered most of the media attention during Discovery's flight, a battery of other experiments have been carried out as well, including investigations mounted on two so-called hitchhiker pallets in the shuttle's cargo bay. For the most part, flight engineer Robert Curbeam said, "both hitchhiker bridges are working very well. In short, without going into each and every experiment, all of them are working well (and) I think we're going to meet all the science objectives." The next major item on the agenda is to recover the CRISTA-SPAS satellite Saturday. The reusable German satellite was launched Aug. 7 for nine days of free flight to learn more about the chemistry of ozone depletion. The satellite and its instruments have worked well, collecting reams of data about the movement of trace gases that affect ozone depletion and the concentrations of hydroxyl and nitric oxide molecules which contribute to the ozone layer's destruction. Preliminary findings from an ultraviolet spectrograph on board the SPAS satellite indicate there is much more wate vapor in the upper atmosphere than can be accounted for by current theory, possibly supporting a controversial new theory that house-size comets are continually bombarding the planet. "The rendezvous is a team effort with all of us on board," said shuttle pilot Kent Rominger. "CRISTA-SPAS is approximately 35 miles behind us right now, and we'll do some phasing burns to raise our orbit to slow us down relative to CRISTA and let us close on it. We actually hop over the top of CRISTA and do a full circle loop, all the way back around it, and we stop and come up from below for a while. And then (we) continue that full circle loop back around to being out in front of it again where we started, except this time we're only 300 feet out in front of it instead of 30 miles. And then we close on in to that final grapple." The rendezvous profile is part of a test to learn more about how precisely the shuttle can be maneuvered for future dockings with the international space station. "When we fabricate the space station, the rendezvous are going to vary quite a bit depending on where we dock with it and what piece we're installing," Rominger said. "Ideally, we'd like to approach it from below because we have natural braking (from Earth's gravity) and we don't have to fire our jets toward the station. "However, there will be cases where we have to come in from the velocity vector (directly ahead of the target), such as we're doing on our rendezvous, and you don't have that natural braking. But yet you have to fire very precisely and try not to impact it. We are deselecting some of our jets as we close in to minimize any kind of thrusting that is going on. This data will be very important to gather to see just how accurately and precisely we can control the shuttle ... on the velocity vector, control the velocity very precisely, within three hundredths of a foot per second." =================================================================== Additional arm tests planned (08/14/97) With their 11-day mission winding down, the Discovery astronauts photographed comet Hale-Bopp again today, took time off to relax and geared up for a busy day Friday making up time lost earlier due to minor computer and communications glitches. Additional comet photography is planned, along with final tests of a Japanese robotic arm that were interrupted Wednesday by communications trouble. Other work includes troubleshooting to fix a Canadian space station experiment computer and additional work with a prototype space radiator that has had its own problems. "Things have proceeded relatively smoothly today, it's for the most part been quiet on board, the crew has had their off duty portion of the mission," said lead flight director Bryan Austin. The major item on the agenda Friday will be a test run with the Japanese Manipulator Flight Demonstration unit in which ground controllers will attempt to remotely operate the compact space crane. "Yesterday, we were hoping to work through and complete our activities with the robot arm," Austin said. "We got pretty close, we extended some of the the crew's day to hopefully finish up some of the ground-commanded operations. But at the end, we had some communication interface problems getting those sequences out to the robot computer. So we'll pick that back up tomorrow, early in the day." Engineers believe a computer froze, or hung up during operations Wednesday, preventing the ground commands from getting through. The system then was powered down and engineers are optimistic the problem will clear itself when the computer system is restarted Friday. "The indications we had from the file transfers, the communications and the error logs between the MFD portion inside and the link outside really indicate we've got something that we just need to recycle the powr on that computer out on the MFD and things should recover quite well," Austin said. "Completing this remaining ground commanded sequence will complete their objectives in full." If problems persist, however, the astronauts will replace the laptop computer being used to control the MFD hardware. Friday is the crew's last chance to complete these experiments. On Saturday, they will rendezvous with and capture the CRISTA-SPAS atmospheric research satellite launched Aug. 7 to study the chemistry of ozone depletion. Then, on Sunday, the shuttle's re-entry systems will be tested and the five-man one-woman crew will pack up for landing Monday at the Kennedy Space Center. Austin said there are no plans to extend the mission. =================================================================== Computer problems interrupt robot arm tests (08/13/97) The Discovery astronauts put a Japanese robotic arm through its paces again today and stood by while ground controllers attempted to operate the small space crane by remote control in a key test of space station technology. Apparent problems with the computer network aboard Discovery used to communicate with the robot arm delayed remote commanding operations and raised the prospect of an additional day's work later in the mission. Such remotely operated equipment is critical for space station operations given all the demands already placed on the spacewalkers charged with building and maintaining the outpost. "We don't really want to go outside on an extravehicular activity unless we have to," said shuttle commander Curt Brown. "Hopefully, this type of arm, or arms like this in the future, will help us have experiments and do maintenance on the outside of the space station, and do that by robotics, therefore not requiring humans to go outside into the vacuum of space." The problem encountered today with the Manipulator Flight Demonstration unit, or MFD, appears to reside "somewhere on board Discovery's network system being used for remote commanding, somewhere in the various payload general support computers that are supporting the flight," said NASA commentator Ed Campion. "There's a PGSC supporting the MFD operations directly," he added. "There's also a PGSC that's supporting OCA operations - orbiter communications adaptor - that's the system that allows software files to be uplinked to the shuttle from the ground. The belief is somewhere in that system of laptop computers and wiring there's something that's hanging us up in terms of being able to get good communications all the way through the system. There's some consideration being given to trying to add some additional MFD operations to the flight day nine (Saturday) timeline. Today had been the final planned day of MFD operations for the flight." Earlier, the crew successfully performed a fourth test operation with the arm earlier today that appeared to go smoothly and officials say a battery of other automated or remotely controlled experiments are continuing to operate as planned with only minor problems. A Canadian project to test a magnetic isolation system intended for space station use also has encountered computer problems, but overall the experiment appears to be a success. In the meantime, the CRISTA-SPAS atmospheric research satellite continues to probe Earth's middle atmosphere, monitoring the movement of trace gases responsible for ozone destruction. As of today, more than 30 sounding rocket- and balloon-borne instruments have been launched in concert with the CRISTA-SPAS projct to help researchers validate the data collected in orbit. The satellite is scheduled to be hauled back aboard Saturday. "We're trying to learn as much as we can about Earth's atmosphere and how we as humans affect that atmosphere," Brown said. "This satellite flew back in 1994 on the STS-66 shuttle mission. I had a chance to take part in that mission, also, and we gathered a lot of data about the ozone, the upper level structure of the atmosphere. This mission, we're going to do the same but they've incorporated a new twist to their satellite. They're able to maneuver their satellite and yaw it left and right to be able to cover more of the Earth's surface. So we'll be able to map more of the ozone and the upper level chemicals and structures of the atmosphere than we did in 1994. "When you put all that data together, we're trying to understand how the Earth's atmosphere evolves over time and how we as humans affect that atmosphere. Obviously, we need that atmosphere to survive and if we are doing something we think may be hurting it, we need to figure out a better way of doing it. The other thing you learn from space is up in the shuttle, if you look at the Earth's limb - the little layer of atmosphere around the Earth - you realize how fragile the Earth really is because it's a very thin body of material that envelops the Earth and protects us from all the harmful emissions from outer space." One final point worth noting in passing today is that engineers discovered some "very slight erosion" in the nozzle used by Discovery's right-side solid-fuel booster. The so-called pocket-wash erosion was found in the area where the forward exit cone attaches to the throat of the nozzle. This is similar to erosion noticed last year after a pair of back-to-back shuttle flights. NASA spokeswoman June Malone at the Marshall Space Flight Center, said engineers probably would not have even noticed the erosion in Discovery's booster nozzle "had we not heightened our awareness of the area." This does not appear to be a significant problem and I mention it here only for the record. =================================================================== Astronauts study Hale-Bopp comet (08/12/97) Astronaut Steve Robinson, operating a seven-inch telescope mounted in the shuttle Discovery's side hatch window, beamed down new pictures of comet Hale-Bopp today, giving project scientists their best look yet at the receding comet. The grainy photographs were less than spectacular to the layman - Hale-Bopp was a small, fuzzy blob that was difficult to even identify as a comet - but scientists say ultraviolet light from the ancient wanderer should provide new insights into its structure and composition. "Back in March or so, Hale-Bopp was nearer to the Earth and nearer to the sun and so we were able to see it more brightly and it had a longer tail," Robinson said. "Now it's about twice as far away from the sun as it was then, so it's not as bright and the tail's not as big. Still, it's relatively close to us and we can see it much more clearly from space because the atmosphere doesn't diffuse the light." While a relatively modest investigation, the Hale-Bopp observations are interesting not only for the scientific data being generated but also for the method being used to obtain them. All of the shuttle's crew cabin windows are coated to block ultraviolet light. But the side hatch of the vehicle has a small, optically clean glass window. The Hale-Bopp telescope is bolted to that window and the shuttle vehicle is then oriented to point the telescope at the comet. Because Hale-Bopp is so close to the sun as viewed from Earth, Discovery's robot arm is being used to shade the hatch window, blocking out as much stray light as possible. All in all, an neat piece of work that demonstrates just how precisely the 100-ton shuttle can be controlled. Otherwise, Discovery's mission continues to proceed smoothly, with all major experiments up and running and no major technical problems to speak of. The CRISTA-SPAS atmospheric research satellite launched last week continues to trail the shuttle by a few dozen miles, training its instruments on the middle atmosphere to learn more about the chemistry of ozone depletion and the global transport of trace gases that contribute to its destruction. Details about the satellite's findings to date can be found in earlier entries. This status report will be updated later this afternoon if developments warrant. In the meantime, here is the morning status report from NASA: STS-85, Mission Control Center Status Report # 12 Tuesday, August 12, 1997 - 6 a.m. CDT Discovery's astronauts spent the first half of their day supporting observations of Comet Hale-Bopp using a small ultraviolet telescope mounted in the side hatch window of the orbiter. Following Stevie Ray Vaughn's "The House is Rockin'" wakeup call from Mission Control, the six astronauts got down to the business of the day, including Mission Specialist Steve Robinson's observations with the small ultraviolet telescope. The experiment, called the Southwest Ultraviolet Imaging System (SWUIS), was used with different filters to gather video and telemetry data on what the comet is made of and how it is responding to solar wind conditions. While Commander Curt Brown and Pilot Kent Rominger maneuvered the orbiter to point its side hatch window toward the comet's location, Payload Commander Jan Davis once again placed the Shuttle's robot arm in a strategic location to provide shading of the window during the telescope's observations. Two more observation days are planned before Discovery's mission comes to a close. Brown and Rominger also watch over orbiter thruster firings and rendezvous maneuvers in support of the CRISTA-SPAS satellite, now in its fifth day of free flight away from Discovery. The orbiter maintains a distance of between 25 and 60 nautical miles from the satellite so that investigators can communicate with the spacecraft using the shuttle as a conduit for the link. In concert with the satellite's on-orbit data gathering, a number of ground-launched rocket and balloon validation flights are being conducted from Wallops Island off the coast of Virginia. In addition to assisting Brown and Rominger with orbiter system oversight, Flight Engineer Bob Curbeam, today continues his work with the Bioreactor Demonstration System designed to perform cell biology experiments under controlled conditions. Canadian Payload Specialist Bjarni Tryggvason, today continues his work with the Microgravity Vibration Isolation Mount which uses magnets to levitate a platform and protect sensitive microgravity processing experiments from vibrations. Discovery's STS-85 crew is scheduled to begin an 8 hour sleep period at about 4:30 this afternoon and awaken at 12:41 Wednesday morning. =================================================================== Robot arm put through paces (filed 08/11/97) Afternoon Update (4:30 p.m.) Despite minor control problems caused by overly restrictive computer software, a prototype Japanese robotic arm intended for space station use has performed near flawlessly, project officials say, setting the stage for remote commanding from Earth later this week. The CRISTA-SPAS atmospheric research satellite launched Thursday, meanwhile, also is operating in fine fashion, collecting data that promises to reshape thinking about the chemistry of ozone depletion. The CRISTA-SPAS satellite is carrying two sets of instruments: A suite of infrared telescopes known as CRISTA and an ultraviolet spectrometer called MAHRSI. The CRISTA experiment is measuring trace gases to learn more about how chemicals that affect ozone depletion are transported through the atmosphere. MAHRSI is measuring levels of hydroxyl molecules and nitrogen oxide, both of which play major roles in ozone reduction. The long-range goal is to improve computer models that predict the response of the atmosphere to changes in the levels or concentrations of industrial pollutants that affect ozone levels. "I'm happy to report to you that since the CRISTA experiment was switched on last week, everything is fine, 100 percent fine," said Derel Offerman, a researcher with the CRISTA-SPAS satellite program. "The three telescopes are working, the four spectrometers are working and the 26 infrared detectors are working." The satellite observations are being carried out in concert with a globe-spanning data collection campaign using ground stations, sounding rockets, balloon and aircraft flights to verify the validity of the orbital data from CRISTA-SPAS. Some 22 ground stations around the world are studying the atmosphere from below as the satellite passes overhead, eight validation rockets have been launched, along with eight balloon flights. In addition, sensors have been flown on an aircraft to measure hydroxyl concentrations over Europe. Hydroxyl, or OH, is made up of one atom of oxygen and one of hydrogen. It is formed when sunlight breaks down water vapor and it is a major natural component of ozone destruction. MAHRSI investigator Robert Conway of the Naval Research Laboratory said Sunday his instrument had detected very high levels of OH in the 80-kilometer region of the atmosphere at high northern latitudes, indirectly confirming earlier data from another NASA satellite about high levels of water vapor in the same region. University of Iowa space scientist Louis Frank has postulated that a steady bombardment of house-size comets, essentially giant snowballs, is releasing water into the Earth's ecosystem. This is a controversial hypothesis at present, but the surprising data from MAHRSI may give Frank additional ammunition. "Measurements over the last four or five years of water vapor in the upper atmosphere show there are abundances there that we can't explain with conventional models," Conway said today. "That's an absolutely fair statement. Now whether or not these comets are the explanation for this amount of water is something we need to work very hard on. There may be indeed other explanations." Then again, maybe not. Details of the initial MAHRSI findings, and background on Frank's data, can be found below in the next entry below. Discovery's systems are operating smoothly with only minor glitches now and then. Overnight, mission control was forced to wake commander Curt Brown because of an avionics problem with a cargo bay suite of experiments called TAS-01. "The orbiter is in very good shape," said Lee Briscoe, a mission operations representative. "The mission management team didn't even meet this weekend because things were going so well. ... Consumables on the orbiter are all OK. The way things are going and the way things are being replanned, right now we're not planning any extension day and we're looking forward to a landing on Monday as planned." As for TAS-01, "we did have a case last evening where the avionics on the TAS payload locked up on us and the only way we had to clear that was to ask the crew to cycle a switch. We waited pretty much as long as we could so we wouldn't have to get them up in the middle of the night but we did wake them up a couple of hours early to cycle a power switch. That basically cleared everything and got all the science ops and laser ops back on track." The Japanese manipulator flight demonstration unit, or MFD, has been operated for three days, simulating the removal of a space station "black box" and opening a small door to precisely characterize the high-tech arm's behavior in space. "Our robot arm moves very smoothly, as expected," said Masanori Nagatomo, a project manager with the Japanese Space Development Agency, or NASDA. "We haven't seen any malfunction in our payload system. We have more than 14 microswitches and every microswitch worked well - this is just as an example - every part of the system is working very well. "We have many sort of restrictions in the robot arm's movements," he said. "If the robot arm's joint moving rate gets high, then our software detects the exceeded rate and makes us stop. During three days of operation, we saw several stops due to such safety features. So I think our system is a little bit sensitive to joint rate or restricted areas." For space station operations, "we should optimize such applications. For some operations, like when grabbing an (orbital replacement unit) or a door, there's no worry (the arm will) run away. In such cases, we can remove some safety features from the software and our logic. If we did so, we can avoid a movement halt due to a safety feature. So the safety features should be optimized to avoid slow operations, including a movement halt, for future applications like space station." Morning Update (11 a.m.) The Discovery astronauts put a prototype Japanese robotic arm through its paces again today, testing its ability to remove avionics boxes mounted on the hull of the international space station. While astronauts Steve Robinson and Jan Davis operated the manipulator flight demonstration unit, of MFD, their crewmates pressed ahead overseeing a battery of other experiments, including a colon cancer cell study, observations of Earth's atmosphere and targets in deep space. "Most of the experiments are going quite well," astronaut Robert Curbeam told a television interviewer this morning. "We have quite a few experiments. The robotic arm, we did some work on that this morning and Steve and Jan are quite pleased by how that went, and we also have a bunch of other experiments looking at Hale-Bopp, the comet, various celestial objects in the solar system, and all of those are going well." Curbeam said the Japanese robotic arm is "just part of the arm that's going on the Japanese Experiment Module of the space station and it's what's called the 'small fine arm.' It goes onto the end of a much larger arm. It is designed to do small, fine tasks, such as removing orbital replacement units, or black boxes, that will be on the outside of the Japanese Experiment Module and also opening and closing doors, things like that. It's about a meter and a half to two meters long and it's designed to do very delicate tasks. And it's working quite well so far." Asked why the astronauts were studying Hale-Bopp, Curbeam said: "The big advantage of being up here in space is you don't have the atmosphere attenuating a lot of the light that Hale-Bopp is giving off. So it's a little bit clearer in different frequencies, especially frequencies that we can't see with the naked eye. By being up here, we can look at the spectral lines the comet is giving off and tell more about what it consists of, what kind of trace elements are in it and hopefully learn more about the formation of our own solar system." Curbeam, a veteran Navy F-14 radar-intercept officer, said Discovery's launch was more exciting than he anticipated based on simulator training at the Johnson Space Center. "There were a lot of surprises," he said. "I was very surprised by how dynamic the whole thing was because the simulator we operate at the Johnson Space Center really doesn't do the trip justice. It's just extremely exciting, I can't describe how great it felt, how at the last minute, we accelerate from about 20,000 feet per second to about 25,000 feet per second and how exhilarating the acceleration on my chest felt. I was just very excited during the whole thing." =================================================================== Shuttle satellite may confirm comet theory (filed 08/10/97) An instrument aboard the CRISTA-SPAS satellite launched Thursday has detected evidence of much more water vapor at high northern latitudes than predicted by current theory, possibly supporting claims that small house-size comets may, in fact, be raining down on Earth. The Middle Atmosphere High Resolution Spectrograph Investigation, or MAHRSI, instrument aboard the CRISTA-SPAS satellite uses an ultraviolet spectrograph to measure concentrations of the hydroxyl molecule - OH - composed of one atom of oxygen and one of hydrogen. Hydroxyl is a major natural component in ozone depletion, which is the primary focus of the CRISTA-SPAS research. The reusable satellite and its instruments flew once before, but during that flight, the spacecraft was not able to study the atmosphere in the high northern latitudes because the sun was too low on the horizon and the research was carried out during winter, not summer. "From the first mission, the OH measurements that MAHRSI made showed a very different form from the predictions of theory," said Robert Conway of the Naval Research Laboratory. "What you have to remember here is no one's ever made these global measurements of OH before, so that mission was a great opportunity to compare the actual results with what theory would predict. And they were very different. "What we saw was a very strong layer of OH at an altitude of about 70 kilometers," he said. "And that wasn't in agreement with the theory. In the meantime, there were some suggestions that maybe there is more water vapor in this high-altitude region. The reason that's important is water is the parent molecule of OH. Wherever there's water and sunlight there's going to be OH, wherever there's OH there WAS water and sunlight. So the two are very linked. "So what we wanted to do was go to these high northern latitudes and see how the layer of OH in this high region of the atmosphere is different. What we're finding on this mission, which has us very excited, is that in fact we find that layer has lifted in the atmosphere at least 10 kilometers. That layer has now peaked at ... 80 kilometers. That has amazing implications. It says that there must be much more water at 80 kilometers than the theory predicted." The new data seems to be supported by other recent findings. Over the past six months, scientists re-analyzing data from an instrument aboard NASA's Upper Atmosphere Research Satellite, launched from the shuttle Discovery in 1991, discovered "much more water vapor at high northern latitudes than they had recognized previously and that the models had any way of predicting," Conway said. Current theory holds that water vapor in the middle atmosphere is blown to high altitudes in tropical thunderstorms. In addition, methane from biological processes also is blown into the middle atmosphere where it breaks down, in a chemical reaction with OH, contributing to water vapor concentrations. Theory says methane and water vapor account for all the hydrogen-bearing molecules in the middle atmosphere. What the UARS data implies, however, is that there's much more water than theory can account for. "What's important about the MAHRSI measurements is that if we, in fact, confirm that we see much more OH in these high latitudes, we in the scientific community have to go back and look at the understanding of water in the middle atmosphere because it simply isn't explained," Conway said. More than 10 years ago, University of Iowa space scientist Louis Frank suggested small comets were regularly bombarding Earth, providing a possible source of water in the upper atmosphere. Few scientists believed him at the time, but in May he provided higher-resolution data from NASA's POLAR satellite that most researchers agree indicate impacts of some sort in the upper atmosphere. Here's how Science magazine described the findings: --------------------- From Science Magazine May 30, 1997 Page 1333 Frank's new data, reported this week at the spring meeting of the American Geophysical Union, come from the Polar satellite, launched in February 1996 to study magnetic fields and charged particles over the poles. This spacecraft carries ultraviolet cameras far better than the one aboard the Dynamics Explorer satellite, which took Frank's first images in the 1980s. Images from the older ultraviolet camera showed dark spots--Frank calls them "atmospheric holes"--no larger than a single picture element or pixel. Everyone except Frank and his University of Iowa colleagues John Sigwarth and John Craven, who is now at the University of Alaska, thought the single-pixel spots were instrumental noise, like snow on an ultraviolet television. Frank and his colleagues, though, interpreted them as places where 80 tons of water had absorbed enough ultraviolet to darken the UV glow of the upper atmosphere. Other researchers are now accepting the reality of the spots, if not Frank's explanation, because the ultraviolet images taken by the Polar satellite have much smaller pixels, and in these views the 50-kilometer-wide spots are 10 to 20 pixels across. The odds that so many randomly darkened pixels could come together to form a spot, all researchers agree, are nil. What's more, the spots show up under different imaging conditions, bolstering the case for their existence. In some cases, Frank and Sigwarth found, the Polar ultraviolet camera caught the same spot in consecutive exposures as the spot moved across the field of view. In other images, spots appeared doubled--as they should have--because Polar wobbled enough that the same object was recorded twice in one exposure. A random dark pixel would appear only once. And one particular spot, says Frank, was caught by both his ultraviolet camera and another on Polar of a different design. Frank also presented observations of a new phenomenon high above the atmosphere that is presumably linked to atmospheric holes: bright trails of water debris. "I just happened to be looking through the images," says Frank, "and all of a sudden saw these bright oxygen trails. We were shocked." About 10 times a day, Frank concludes, an incoming small comet between 5000 and 50,000 kilometers leaves enough water in its wake that sunlight dislodges a trail of oxygen atoms from the water. Frank's final line of evidence is visible-light images showing hydroxyl, another fragment of water. These trails appear at altitudes of 2000 to 3000 kilometers, just above where small comets are supposed to disrupt to form atmospheric holes, and the trails seem to be about as abundant as atmospheric holes, says Frank. "That's totally independent verification of the ultraviolet measurements," he says. --------------------- There is no agreement yet on Frank's conclusions and its much too early to know if the MAHRSI data ultimately will buttress his argument. But it is certainly intriguing. "It's very provacative," Conway said. "It doesn't mean that's what's happening, but it certainly opens the question and it certainly puts the burden on us to explain where the water is coming from." With CRISTA-SPAS trailing the Discovery and operating smoothly, the shuttle astronauts spent the day carrying out more tests of a high-tech Japanese robotic arm intended for use on the international space station. The prototype aboard Discovery appears to be working better today after initial problems Friday that were blamed on computer control software that constrained the arm's movement. A suite of other experiments aboard Discovery also is collecting data on topics ranging from fluid physics to ultraviolet astronomy. Here's NASA's morning status report from the Johnson Space Center: --------------------- STS-85 Mission Control Center Status Report # 07 Sunday, August 10, 1997 - 6:00 a.m. CDT Following this morning's wakeup call at 1:40 a.m. CDT, Discovery's astronauts focused their attention on testing of a small, robotic arm serving as a prototype for use on the future International Space Station and conducting experiment work on the Shuttle's middeck. While the free-flying CRISTA-SPAS satellite continues to gather data on the Earth's atmosphere and ozone layer, Payload Commander Jan Davis and Mission Specialist Steve Robinson once again will spend the day testing the small Japanese robotic arm. Their work began about 5:30 this morning with Robinson operating the arm through a checkout and then detachment and reattachment of a box simulating an orbital replacement unit. The arm's dexterity will further be tested remotely from inside the crew compartment by opening and closing a door on another box. After lunch, Davis and Robinson will swap places with Davis operating the arm through an identical checkout with Robinson supporting the activity. Mission Specialist Bob Curbeam continued his work with the Bioreactor Demonstration System designed to perform cell biology experiments under controlled conditions. Canadian Payload Specialist Bjarni Tryggvason continued his work with the Microgravity Vibration Isolation Mount which uses magnets to levitate a platform and protect sensitive microgravity processing experiments from vibrations. Such a system could be valuable on a space station to protect materials processing experiments from vibrations caused by other activities. Periodic firings of Discovery's thrusters continue at the beginning and end of each crew day by Commander Curt Brown and Pilot Kent Rominger to maintain a desired distance of 25 to 45 nautical miles from the CRISTA-SPAS satellite. The spacecraft will be retrieved a week from today for the return trip home. =================================================================== Shuttle satellite sniffs out volcano; crew studies comet (filed 08/09/97) The shuttle Discovery's astronauts trained a sophisticated ultraviolet telescope on comet Hale-Bopp today and pressed ahead with a smorgasbord of other experiments. Instruments aboard the German science satellite launched Thursday to study Earth's atmosphere also is working well, monitoring 18 trace gases and their global transport to learn more about the chemistry behind ozone depletion. Engineers believe problems with a Japanese robotic arm being tested aboard the shuttle will be corrected after control software is revised to give the arm more room to operate. Additional tests are planned Sunday. A mission science briefing is scheduled for 2 p.m. today and this status report will be updated after its conclusion. Astronaut Stephen Robinson spent the afternoon studying comet Hale-Bopp using a seven-inch telescope attached to the shuttle's side-hatch window. Because the comet is so close to the sun as viewed from Earth, astronaut Jan Davis precisely positioned Discovery's robot arm to shadow the side hatch in a bid to improve the view for the telescope. Nonetheless, it appeared to be a challenging observational task. "I was able to see the comet a couple of hours ago visually,," Robinson said before beginning the telescopic observations. "It was a very, very faint target to my eye and I was not able to get the binoculars on it in time. ... There's a lot of earthshine. Jan has done a really good job putting the shadow right over the window (but) there's a tremendous amount of earthshine. We'll just have to see how that works." A few moments later, as Discovery was passing south of Australia in orbital night, the first images from the telescope were downlinked to Earth showing the fuzzy comet in ultraviolet light. These were rather unspectacular images compared to the visual-light photos familiar from Hale-Bopp's springtime passage through the inner solar system, but ultraviolet observations are useful to astronomers because UV radiation from astronomical targets cannot pass through Earth's atmosphere. Derel Offerman, a researcher with the CRISTA-SPAS satellite program, said the spacecraft, launched Thursday, had been checked out and "we have begun measurements in the atmosphere. The CRISTA instrument is 100 percent OK and we are measuring simultaneously all of these 18 gases." Responding quickly to monitor the effects of a volcanic eruption on the small Caribbean island of Montserrat, scientists have set up a special observation program "to check whether we can see any influences on the upper atmosphere of the volcano," Offerman said. "If these type of volcano explosions are very strong, then they reach the higher atmosphere, that means up to 20 kilometers or even higher, and we should be able to see that. We have set up a special observation program to continuously monitor the area around Montserrat and check whether we can see any influences." According to Reuter, the Soufriere Hills volcano has virtually destroyed the island's abandoned capital and sent clouds of ash as high as 40,000 feet, or about 12 kilometers. The satellite is equipped with two suites of instruments: A trio of supercooled infrared telescopes - CRISTA - and an instrument sensitive to ultraviolet reflections and emissions, known by the acronym MAHRSI. Robert Conway of the Naval Research Laboratory, explained today why the research is important. "These trace gases are truly tracers in the sense that they give us evidence at every altitude in the atmosphere for the physical processes that are going on there," Conway said. "We have a general idea of the physics that controls the flow of gas from the lower atmosphere up through the tropopause into the stratosphere and then disperses those gases throughout the globe. That process of transport, or dispersal, is controlled by the heating and the cooling of the atmosphere during the day, it's controlled by the position of the sun above the planet as the seasons vary. We can learn an immense amount about ... the way the atmosphere works by watching these trace gases through different seasons and different times of day. "That's important because as everyone knows, the industrial activities of mankind put pollutants into the atmosphere and these pollutants will reside in the atmosphere for who knows how long," he said. "It's an open question, what is the age of air at any level in the atmosphere? It passes from a very active layer where there's lots of thunderstorms, a lot of weather, it punches through the tropopause and then how long does it reside there? How long does it take to go from the equatorial regions to the poles? These are all open questions and that's the reason we ... are so excited to look at these measurements." Offerman and Conway, chief of the MAHRSI team, said both sets of satellite instruments are operating flawlessly with no repeats of any communications glitches like those experienced Thursday (see the CBS Reporter's Notebook below for details). In other shuttle news, program managers have rescheduled the shuttle Atlantis for launch to the Mir space station on Sept. 27. Liftoff originally was planned for Sept. 18, but the flight was delayed to give astronaut David Wolf time to complete a crash course in use of the Russian Orlan spacesuit. Liftoff now is targeted for 9:46:43 p.m on Sept. 27 with docking at 5:37 p.m. on Sept. 29 (MET 1/19:50). Undocking will take place at 3:11 p.m. on Oct. 5 (MET 7/17:24) and the shuttle will land on Oct. 7 (time TBD). Program managers are protecting a "no earlier than" launch date of Sept. 22 if a crisis develops aboard Mir that demands an earlier takeoff. But the actual target date is Sept. 27, two days after launch of an Atlas rocket carrying a commercial payload. If the Atlas launch slips a day, Atlantis's flight will slip a day as well. Here are the shuttle's launch windows through Sept. 30: DATE......WINDOW OPENS.....WINDOW CLOSES....DURATION (mm:ss) 09/27.....09:46:43 p.m.....09:56:41 p.m.....09:58 09/28.....09:21:04 p.m.....09:34:10 p.m.....13:06 09/29.....08:58:29 p.m.....09:08:27 p.m.....09:58 09/30.....08:35:55 p.m.....08:45:53 p.m.....09:58 A Russian Progress resupply vehicle, originally scheduled for launch Oct. 1, is currently targeted for Oct. 4. Given the new launch date for Atlantis, however, the Progress launch likely will slip to Oct. 5, the day shuttle undocks from Mir. The Progress would dock two days later. As for operations aboard Discovery today, here is the morning status report from the Johnson Space Center: STS-85 Mission Control Center Status Report # 05 Saturday, August 9, 1997 - 6 a.m. CDT Serving as a testbed for those ISS evaluations, the orbiter is functioning in excellent fashion while the crew gathers data using the Space Vision System - a series of dots strategically placed on various payload and vehicle structures that permit precise alignment and pointing that could be invaluable on the space station when a clear line of sight by the crew is not available. In addition to SVS, the crew is evaluating a system designed to dampen vibrations that could be harmful to sensitive science experiments. The Microgravity Vibration Isolation Mount, or MIM, also can induce vibrations that scientists can use to determine what effects those vibrations have on experiment operations. It will be operated throughout the day by Canadian Astronaut and Payload Specialist Bjarni Tryggvason. While Payload Commander Jan Davis focused on SVS operations, Mission Specialist Steve Robinson worked with a controlled-flame investigation called the Solid Surface Combustion Experiment. Robinson also will setup and operate a small ultraviolet imaging telescope to view Comet Hale-Bopp. The shuttle's robot arm will be strategically placed to provide shading of orbiter windows during the telescope's observations. Mission Commander Curt Brown and Pilot Kent Rominger continue to periodically fire thruster jets on the orbiter to maintain an adequate distance from the free-flying CRISTA-SPAS satellite which was deployed on launch day. The satellite will gather atmospheric data, including ozone measurements, that will be useful in calibrating other ground-based instruments. Flight Engineer Bob Curbeam will spend his day assisting with the Space Vision System and Hale-Bopp observations, while overseeing work with the Bioreactor Demonstration System, which will evaluate a cell culture incubator and a biotechnology specimen temperature controller. Cell biology experiments in space could lead to the use of microgravity to manufacture tissues from individual cells. =================================================================== Engineers track down communications glitch (filed 08/08/97) The Discovery astronauts began testing a high-tech Japanese robot arm today, a prototype for an arm that will be mounted on the international space station. Earlier in the day, engineers on the ground implemented a revised experiment commanding strategy to eliminate conflicts between different payloads that caused problems Thursday, including a delay in the launch of the CRISTA-SPAS atmospheric research satellite. Checkout and activation of other on-board experiments also was delayed. The satellite deployment was held up about a half hour when engineers were unable to get the proper commands through the shuttle's computer system to the satellite and its instruments. Occasional communications glitches persisted after the spacecraft was released into open space. Lee Briscoe, mission operations representative at the Johnson Space Center, said the problem commanding the CRISTA-SPAS satellite and other experiments was similar to the trouble on-line subscribers occasionally experience when too many people try to access the service at one time. "With all the experiments commanding simultaneously, there was a little bit of command interference between the payloads," he said. "On this particular flight, we have some new capabilities in the software. We knew this flight was going to be command intensive. In the past there's only been one path, if you will, through our systems management computer software to get out to the payload. For this particular flight, we added a new pathway through that software specifically for payloads and we call it the payload throughput buffer. In the past, the payloads and the systems folks who manage the orbiter systems had to share a single command buffer called our two-stage command buffer. So they had to share that. The old two-stage command buffer system was designed to accept a command, acknowledge receipt and then execute the command in the order it was received. "It was a slow but useable technique," Briscoe said. "As more and more people started commanding and wanting command capabilities and ground interface, we thought it would be a good idea to put in that separate pathway. So we put in this new payload throughout buffer to allow the payloads to do all their commanding through that and not have to necessarily go through the kind of routine we were doing when we used the other buffer. Then the two-stage buffer would be free for orbiter use. "So this was the first time we were using that new capability and we have three payloads (CRISTA-SPAS, a suite of ultraviolet astronomy instruments and a package of other experiments) on there that are commanding a lot. And one of the things we discovered is that as everybody was trying to command at once we were getting some data rejects as they went through that buffer. So it slowed down the commanding a little bit and it took a little while to figure out exactly what was going on there. The solution worked out early today calls for the CRISTA-SPAS satellite to use the payload throughput buffer. The other two sets of experiments in Discovery's cargo bay will use the older two-stage buffer. "In addition, we slowed down our command rate just a smidgeon just to see if that would help and that all appears to be working pretty good now," Briscoe said. "It looks like now everybody's getting their commands through, we're not having data rejects in the payload throughput buffer and folks are on their way to getting everything configured." While several experiments are running behind schedule because of the earlier problems, Briscoe said most were catching back up now that the problem has been resolved. =================================================================== Shuttle Discovery rockets into orbit (6:30 p.m., 08/07/97) The shuttle Discovery rocketed through a hazy, partly cloudy sky and into orbit today to kick off an 11-day science and technology development mission focused on learning more about the chemistry of ozone depletion. Launch of the CRISTA-SPAS atmospheric research satellite was delayed a half hour or so by a communications glitch, but at 6:27 p.m., the small spacecraft was released into open space. "Houston, Discovery, CRISTA is deployed," radioed commander Curt Brown as the two spacecraft sailed 160 nautical miles above the north Pacific Ocean south of Alaska. "We copy," replied astronaut Ellen Ochoa from mission control in Houston. With Brown and pilot Kent Rominger at the controls, Discovery lifted off on its 23rd mission at 10:41 a.m., right on time, after a relatively problem-free countdown. Eight-and-a-half minutes later, the shuttle slipped into its planned preliminary orbit and a half-hour after that, Brown fired Discovery's orbital maneuvering system engines to circularize the orbit at an altitude of 160 nautical miles. "The weather behaved very nicely for us," said Donald McMonagle, chairman of NASA's mission management team. "The vehicle was very clean. We've only had one very minor anomaly, and that was loss of an open descrete on a valve, and that's absolutely no impact because the valve and the RCS jets associated with that are usable. So this is about the cleanest we can expect from a vehicle and everything has gone extremely well." The primary goal of the 86th shuttle mission, Discovery's 23rd flight, is the launch later today of a small reusable German science satellite carrying a pair of instruments that will be trained on Earth's atmosphere to learn more about the chemical and physical processes that contribute to the destruction of the protective ozone layer. Other mission objectives include 20 hous of tests of an $80 million prototype Japanese robot arm intended for use aboard the international space station; observations of deep space targets using a suite of ultraviolet instruments; other Earth observation studies, protein crystal growth experiments, research in basic physics and biological studies. Several technology development projects are on board and the flight even features a modest program to study the Hale-Bopp comet above the obscuring effects of Earth's atmosphere. Mission STS-85 "is an example of a mission that's just jam-packed full of activities," Brown said during a pre-launch news conference. "85's also a perfect example of the versatility and the capabilities of the space shuttle program and the shuttle orbiter itself. One word for 85 I'd say would be diversity. We have about everything. We have over 40 different payload activities on board. These payloads are from six different countries and are supported by many different colleges and universities all around the world. Not only do we have a large number of activities on 85, but we also have a broad spectrum of activities." Joining Brown and Rominger aboard Discovery are flight engineer Robert Curbeam, payload commander Jan Davis, astronaut Stephen Robinson and Canadian astronaut Bjarni Trygvasson. Curbeam, Robinson and Trygvasson are shuttle rookies making their first flight. Tryggvason was born in Iceland and Icelandic President Olafur Ragnat Grimsson, who watched the launch from the Kennedy Space Center, said the flight "absolutely thrilled" his countrymen, calling it a "major event." "We are a culture of settlers created from the old days of the sagas and we see Bjarni Tryggvason as a direct descendent of the great discoverers of the Viking period," Grimsson said. "Therefore, I think it's almost a divine indication that the name of the space shuttle should also be Discovery." Rominger, known by his nickname "Rommel," celebrated his 41st birthday with today's launch. "Rommel, happy birthday. We're about to light your candle," a launch controller radioed moments before blastoff. "Well, thanks for that birthday wish," Rominger laughed. "It'll be the two best candles I ever had." The CRISTA-SPAS satellite originally was scheduled for deployment seven hours after launch, shortly before 6 p.m. But a communications glitch prevented ground controllers from getting commands into the spacecraft. After troubleshooting, the crew was asked to shut the satellite down and to power it back up. That apparently reset the spacecraft and launch was rescheduled for 6:27 p.m. If all goes well, the satellite will operate on its own over the next nine days before being hauled back aboard for return to Earth. Given the shuttle's orbit, carrying it and the satellite 57 degrees to either side of the equator, CRISTA-SPAS will map most of the planet's atmosphere over the course of its flight. "The idea is to look at the photo-chemistry of Earth's upper atmosphere," said Robinson. "A growing population of humans on Earth is affecting our atmosphere and if we want this Earth to be a home for us in the future, e have to understand what sort of effects we're having on the atmosphere and learn to deal with the negative effects that we're making happen." One instrument aboard the SPAS satellite, called CRISTA for Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere, is made up of three heat-sensitive instruments that will measure infrared emissions, taking the temperature of the middle atmosphere. The other instrument, the Middle Atmosphere High Resolution Spectrograph Investigation, or MAHRSI, will measure ultraviolet radiation reflected and emitted by the atmosphere. Working in concert with the satellite during its 200 hours of free flight, scientists on the ground will study the same regions of the atmosphere using balloon-borne instruments and sounding rockets. If all goes well, the CRISTA-SPAS satellite will be hauled back aboard Discovery on Aug. 16, two days before the shuttle returns to Earth. "Ours is really the first generation with the tools to understand the environment, with the information systems, with the technologies," said Mike Mann, deputy associate administrator of NASA's Mission to Planet Earth program. "And we have a responsibility not only to ourselves but to our children, to apply those tools, including the space shuttle, including these sophisticated instruments, in every way we possibly can to understand the environment. "This particular mission is largely focusing on the atmospheric processes that govern ozone depletion," he said. "That's obviously critical because the ultraviolet rays that are hitting the ground affect plant growth, affect humans. It's really understanding those atmospheric processes that are critical to sustaining life as we know it." Mission scientist Jack Kaye said current computer models about ozone depletion in the mid latitudes tend to under predict the actual loss. Data from the CRISTA-SPAS satellite, along with the results of balloon and rocket flights, should help clarify how trace gases that affect ozone levels are transported from one region of the atmosphere to another. "The information on the details of transport processes in the lower stratosphere that we get from CRISTA will really be unique," Kaye said. "That's one of the interesting scientific questions right now is how do meteorological processes in the upper atmosphere connect different regions of the atmosphere, how do things that get into the tropics get into mid latitudes and how do things in the mid latitudes mix into the tropics. CRISTA really lets us look at the details of connection between different regions of the atmosphere over a range of altitudes better than anything we've had in the past." The ultimate goal of such research, Kaye said, is to improve computer models enough to provide lawmakers with accurate forecasting to help them decide what sort of regulation is needed to control depletion. "If you under regulate the impact is (costly)," he said. "If you over regulate, the economic costs to the economy could be very, very severe. So you've got to have the best possible scientific underpinning for these assessments. And that's really what we're trying to do, insure the highest possible scientific underpinning. Then hopefully, the decision makers in the international community can reach the right conclusions about what to do about that." During the rendezvous to recover the CRISTA-SPAS satellite, Brown and Rominger will carry out what amounts to a space station docking maneuver, duplicating the procedures planned for latching onto the international space station. Other station-related exercises also are planned, including work with the shuttle's Canadian-built robot arm and Canadian-developed computerized space vision system that will be used to precisely position the big space crane. Davis will practice moving the arm in the same pattern required for the first few station assembly flights. On flight day 11, "we'll actually be doing the (robot arm) maneuvers for building space station flights 2A, 3A, 4A and 5A, gathering data on how we can ue these vision systems to assemble the space station on those flights," Davis said. "We'll also be characterizing how we'll be able to do this vision system with different lighting conditions, we'll be using some sophisticated methods of looking at low-light conditions and how well the targets can be viewed under those conditions." =================================================================== Shuttle countdown update (filed 08/06/97) Afternoon Status Report (4 p.m.) NASA managers met today and formally cleared the shuttle Discovery for blastoff Thursday on a satellite launching mission to study Earth's atmosphere and the processes that control ozone depletion. At a traditional pre-launch news conference, shuttle program manager Tommy Holloway said the launch team is on track, weather permitting, for an on-time blastoff. "We have a very interesting flight on STS-85," he said. "We have something for everyone. I think the flight crew's soing to have an extremely busy and rewarding time. We're looking forward to a launch tomorrow and a successful flight." Forecasters continue to predict a 60 percent chance of acceptable conditions, with partly to mostly cloudy skies, winds at eight to 12 knots and visibility of seven miles. "For the most part, things look pretty good for tomorrow, but there are a few potential concerns we're going to be monitoring between now and then," said Air Force Capt. Scott Jacobs, a shuttle weather officer. "With a cold front moving into north Florida today and the moist, unstable air mass already in central Florida, our primary concern for tomorrow is going to be the potential for some showers popping up in and around the area. But hopefully, with the window opening at 10:41 a.m., we will be able to get off early enough before the typical afternoon (storm) activity begins." See below for a detailed timeline of upcoming events. Otherwise, this status report will be updated at 6 a.m. Thursday or as conditions warrant. Morning Status Report (8:30 a.m.) Keeping close tabs on threatening weather, engineers at pad 39A are pressing ahead with final preparations to ready the shuttle Discovery for blastoff Thursday at 10:41 a.m. on a 10-day science mission. Forecasters continue to predict a 40 percent chance of showers or thunderstorms during the shuttle's one-hour 39-minute launch window that would delay the flight. "Overall, the STS-85 countdown is basically proceeding per schedule, we're right about where we want to be at this time of the morning," said NASA test director John Guidi. "We have no technical issues, everything's counting down very smoothly and we're ready to go." Engineers plan to roll a protective gantry called the rotating service structure, or RSS, away from Discovery at 4:30 p.m. NASA's mission management team will meet at 1:15 a.m. Thursday to assess the weather and to give a "go" for fueling to being at 1:50 a.m. But shuttle weather officer Ed Priselac says afternoon thunderstorms likely will delay RSS rollback and there's a 10 percent chance of overnight thunderstorms that would delay tanking. "We've got copious tropical moisture in the area," he said. "The air mass is unstable both day and night. We've had thunderstorms off the East Coast and along the West Coast of Florida every night." There are several issues that could affect Discovery's launch Thursday. A rare August cold front moving toward Florida is expected to remain north of the launch site, but given the unstable nature of the upper atmosphere and all the moisture present, showers may develop in the morning hours. "We've got four different computer models we're looking at and they all give us a different solution," Priselac said. "One actually has the front south of us, which we don't believe. But it looks like the front itself will remain to the north of us. However, what we'll have over the peninsula is a number of outflow boundaries that remain dormant overnight. [There is a chance for] some of these east-west bands of showers or thunderstorms forming and that's the main concern for tomorrow morning." The forecast for Friday calls for a 70 percent chance of acceptable launch weather. =================================================================== Shuttle countdown update (filed 08/05/97) The shuttle Discovery's countdown continues to tick smoothly toward a liftoff at 10:41 a.m. Thursday on a 10-day science and technology research mission. There are no technical problems at pad 39A and the only question mark remains the weather. Forecasters are predicting a 40 percent chance of low clouds and showers associated with a cold front that could delay blastoff. "Everything's been going well from a technical perspective, we really have no issues affecting the management team at this time," said NASA test director John Guidi. "Everything's looking really well. So we'll just be looking at the weather." Shuttle weather officer Ed Priselac said movement of the front in question, which is slowly but surely approaching Florida from the north, is difficult to predict. If it dips down as far as central Florida, stormy weather can be expected. If it remains north of the spaceport, conditions should be acceptable for launch. "We almost need to go to the Psychic Friends network to determine just where the front's going to be," Priselac said this morning. "We're getting hints from a couple of [computer] models today that the upper flow will move back just a bit north, which would tend to push the front back a bit north of us. And we've got a couple of long-range models that suggest the front's going to be very close to us tomorrow. Right now, we're suggesting the front will be somewhere around Daytona Beach, a little north of us, and that's our best scenario. If the front gets over us or south of us, then we're going to have more issues with regard to low clouds and showers in the area." The forecast for Friday and Saturday remains 70 percent "go," although Priselac said computer models indicate the possibility of an off-shore low pressure system that could cause deteriorating conditions Friday. Discovery's one-hour 39-minute launch window opens at 10:41 a.m. Thursday and closes at 12:20 p.m. The opening of the window assures multiple daylight landing opportunities at the end of the mission. The close of the window is set by the scientific objectives of the CRISTA-SPAS atmospheric research satellite that will be launched and later retrieved by Discovery's crew. It may be possible to extend the launch window Thursday if bad weather does, in fact, materialize, but that would require approval by the research community as well as the shuttle launch team. Discovery's five-man one-woman crew, dodging afternoon thunderstorms in central Florida, arrived at the Kennedy Space Center at 5 p.m. Monday to begin final preparations. "We had to fight mother nature just a little bit to get down here this evening," commander Curt Brown told reporters. "We took a little flyby of the pad to take a look at the vehicle ... it's a very clean vehicle and Discovery is ready to go. So we're really happy to be down here again ... for the real thing." ===================================================================