A SpaceX Falcon 9 rocket was erected at the launch pad Monday for an overnight flight, weather permitting, to boost an EchoStar communications satellite into orbit.
Mounted horizontally atop a transporter-erector, the 229-foot-long rocket was hauled from its hangar at the base of launch pad 39A at the Kennedy Space Center early Monday and then hydraulically rotated vertical to set the stage for takeoff from the repurposed space shuttle pad.
Liftoff is targeted for 1:34 a.m. EDT (GMT-4) Tuesday, the opening of a two-and-a-half-hour window. Forecasters are predicting a 40 percent chance of acceptable weather due to potentially thick cloud cover. A second launch opportunity is available Thursday if the weather or a technical issue prevents takeoff Tuesday.
Unlike recent SpaceX flights, there are no landing legs on the Falcon 9’s first stage. Because of the weight of the EchoStar-23 satellite and the requirements of its initial orbit, the rocket will not have enough propellant left over to attempt a landing on an off-shore droneship. Instead, the stage will fall back into the atmosphere and break up, the traditional fate of a fully expendable rocket.
This will be the California rocket builder’s third launch of a Falcon 9 since a spectacular explosion Sept. 1 at the nearby Cape Canaveral Air Force Station that destroyed another booster and its $200 million satellite payload, heavily damaging launch complex 40.
The mishap was blamed on a ruptured high-pressure helium tank inside the rocket’s second stage liquid oxygen tank. Corrective actions were implemented and SpaceX returned to flight Jan. 14, successfully launching 10 Iridium NEXT satellite telephone relay stations from Vandenberg Air Force Base, Calif.
The company then launched a space station cargo ship from pad 39A at the Kennedy Space Center on Feb. 19, the first flight from the historic complex since the shuttle Atlantis took off on the program’s final mission in July 2011.
Hoping to make it three in a row -- the second in a row from pad 39A -- SpaceX engineers test fired the EchoStar Falcon 9’s first-stage engines last Thursday to set the stage for launch Tuesday.
The EchoStar-23 satellite will be boosted into an initially elliptical orbit by the Falcon 9. On-board propulsion then will be used to circularize the orbit at an altitude of 22,300 miles above the equator. In such “geostationary” orbits, satellites take 24 hours to complete one trip around the planet and appear stationary in the sky -- a key requirement for communications stations.
Built by Space Systems/Loral of Palo Alto, Calif., the EchoStar-23 satellite “is a highly flexible, Ku-band broadcast satellite services (BSS) satellite with four main reflectors and multiple sub-reflectors supporting multiple mission profiles,” SpaceX said in a mission press kit.
EchoStar, based in Englewood, Colo., operates 25 geosynchronous communications satellites. The company originally hoped to have EchoStar-23 in orbit by the end of 2016, but the flight was delayed in the wake of the Sept. 1 launch pad explosion.
If all goes well, SpaceX hopes to launch an SES communications satellite around March 27, the first flight of a “used” Falcon 9 first stage.