NASA Administration has nixed an upcoming upgrade and maintenance mission to Hubble Space Telescope, dooming it, and scientists are up in arms. Without more fuel for its controllers, the orbiting telescope can't be properly controlled, and without a scheduled upgrade, it won't improve. Sixty Minutes (the TV show) is up in arms. Hubble is arguably NASA's most successful program (arguably), and certainly one of its most expensive ones. With maintenance and new instrumentation, the Hubble's best days would otherwise still be ahead of it, as past upgrades have proven very successful, and more were planned.
The reason Hubble may perish isn't so much President Bush II's sharp budget reductions to regular NASA programs in order to concentrate on a mars shot, but safety. Hubble is in low orbit, but nonetheless, a higher orbit than the Space Station. A rescue mission to or from the Space Station is quite possible (it's supposed to have a rescue re-entry vehicle with it at all times), but the extra energy to get to the Hubble makes a direct rescue mission impossible right now. Therefore, NASA has decided it can't risk the Shuttle astronauts lives by sending the Space Shuttle up to the Hubble's higher orbit anymore, given what it now knows about how fragile the Shuttle is.
So how about having the Shuttle carry only two astronauts when it goes to Hubble, and also take with it a small inter-orbital craft designed only to get from Hubble down to the Space Station, if necessary. Such a vehicle could be quite simple, and light - no heat shields would be needed. It would be designed to get two astronauts back to the Space Station one time, where they could be rescued, if need be.
A collapsible vehicle with an inflatable crew cabin might be possible, with modern materials, which would take up little space in the Shuttle's payload bay, and if perhaps some part of the astronauts oxygen supply could be made portable, from the shuttle to this rescue vehicle, that would lighten any extra load still further. Even better, although perhaps too ambitious: if this rescue vehicle could be connected to the Shuttle's fuel supplies so that it's tanks could be pumped full in an emergency and then disconnected, that would further decrease the additional burden on the Shuttle's lifting capacity, or the effective payload it could lift up to Hubble.
At worst, it might be necessary to make one extra trip to the Hubble Space Telescope only in order to deliver such a rescue vehicle to the telescope, or perhaps to an orbit very close to it, where even an injured Shuttle could easily maneuver to it.
As smartalix has pointed out, such a transorbital vehicle, or sled, might also prove useful once large-scale projects begin.
For more about this controversy, and what you can do, see also: www.savethehubble.com