Two Shuttles
Published on May 10, 2009 at 8:12 pm.
4 Comments.
Filed under space shuttle.
In less than a day, a rare sight will come to an end at the Kennedy Space Center: two Space Shuttles sitting on launch pads at the same time.
When Launch Complex 39 was built at the Kennedy Space Center, plans allowed for a full blown spaceport. There were plans for four launch pads supported by centralized facilities. At one point, it seemed that NASA would be launching rockets every few days. In only a decade, we went from sending a man barely out of the atmosphere to going to the Moon. There was talk of a permanent manned moonbase, multiple Earth-orbiting space stations, and a manned mission to Mars … all by the 1990s. If things had kept going at the pace that they were in the 1960s, and if NASA had kept the funding level that they had then, these things might have been possible. KSC was designed with the possibility of expanding to permit the sort of continual launches that such activity would require. Ultimately, only two of the original planned launch pads were constructed. In the early days of the Space Shuttle program, there was (overly optimistic) talk of perhaps a launch per week. Such a schedule would have likely required building more of the launch pads. But, the Shuttle program never panned out where it needed additional launch capacity. In fact, there have been only a few times when both launch pads have been in use at the same time.
In the image above, Space Shuttle Atlantis sits on pad 39A ready to lift off tomorrow on STS-125 mission to the Hubble Space Telescope (HST). After the loss of the Columbia, NASA deemed the launch of the Space Shuttle to be more hazardous than they had been feeling that it was. A mission to the International Space Station (ISS) could stay there for a while if the shuttle was damaged during launch. Additional food, water, and supplies could be sent to the ISS to support the astronauts for as long as it took to send another Space Shuttle to retrieve them. But, if the shuttle were sent to the HST, then it would be in an orbit that could not reach the ISS. The shuttle carries just enough fuel to do its mission, and it could not change orbits enough to get from one to the other. So, if it were damaged on liftoff, then the astronauts would run out of food and water. That is, they’d run out of food and water unless a rescue mission were launched. That would require another spacecraft capable of reaching the HST and capable of carrying sufficient crew to retrieve the crew members of the damaged shuttle. That is why there are two Space Shuttle sitting on both of KSC’s launch pads. If Atlantis is damaged on liftoff, Endeavour is sitting ready on launch pad 39B to match orbits and rescue the crew of Atlantis.
The contingency mission to rescue the crew of the STS-125 mission is designated STS-400. It is out of the regular numbering sequence, and it may never be flown. Endeavour will only lift off on STS-400 if Atlantis is damaged and cannot return safely on its own. If Endeavour does not need to be launched for STS-400, then plans are to move it to pad 39A once it is determined that it will not be needed. It will then be used for the STS-127 mission to the ISS next month. If it does launch as STS-400, the future planned missions to the ISS are in doubt. It is also interesting to note that the training for the different missions is, of course different, so a different crew would take Endeavour up for STS-400 than would fly for STS-127.
Whatever happens, once Endeavour is no longer sitting on pad 39B, that launch pad will be decommissioned from further Space Shuttle use, and the conversion of the launch pad to permit use for the Constellation program will resume. If Atlantis launches on schedule tomorrow, then it will be the last time that two Space Shuttle are on launch pads at the same time. It is not the first time that this has happened, and it is the not the first time that a rescue rocket has been available. I remember that during the Skylab missions, NASA had a rescue rocket ready to go. A space rescue has never been required, but the idea is not unprecedented.
-Astroprof
Image courtesy NASA
Astronomy Link List on May 11, 2009 at 10:23 am: 1
This article has been added to the Astronomy Link List.
Sili on May 11, 2009 at 12:27 pm: 2
Sic transit and so on and so on.
Such a pity that noöne wanted to pay. What a world I could have grown up in.
Astroprof’s Page » The most dangerous launch, ever??? on May 11, 2009 at 4:10 pm: 3
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sophia on May 23, 2009 at 2:50 am: 4
Very informative post it was fun to read it..thanksss