I think they’re also well-trained to deal with snags and failures, and to come up with on-the-spot solutions if that’s possible. There have been a number of cases (certainly with ISS construction, if not with previous HST missions) where astronauts have had alter plans in mid-mission and come up alternative approaches. It wouldn’t surprise me at all if missions which went exactly as planned were the exception rather than the rule, and that the astronauts are well aware of this.

The Hubble could not be attached physically to the ISS. The ISS is a large multi-mode vibrational structure, which would prove to be horrible.

Bringing the Hubble back to Earth is not likely either. The flight dynamics of the ship would be very different and more difficult with a large payload on board. It would be a very risky venture.

Lawrence B. Crowell

The astronauts are being trained up so that mental decisions, body motions, and technology operate perfectly according to a script. It looks as if anything that could go wrong could hex the Hubble Telescope for good. I am not privy to the inside information on this, but maybe there needs to be reconsideration of the whole protocal.

Lawrence B. Crowell

Re-entry with that much additional weight – wouldn’t this even be possible?

Yes, it must be possible. Hubble was launched on the Shuttle and they must have had the option to re-enter with it still on board in case there was a problem with deployment.

Back in the days when they used the Shuttle to launch multiple satellites they took care to release them in the right order so if the second (or third?) failed to deploy after the first (or second?) had been released the centre of gravity would be in the right range for re-entry and landing. If the first had failed to deploy then it would have been, literally, suicidal to attempt to release the second.

Concerns about folding it up (particularly the replaced solar panels – remember that the panels on it now are not the ones which folded out after its initial release from the Shuttle) and issues of contamination sound very real to me, though.

And I think it actually would be impossible to get it down to Earth and back up without an unacceptable level of contamination, which would then outgas and cause all sorts of problems. Yes, everything on Hubble started from Earth, but it went from a clean room to the launch vehicle to orbit.

I suspect a real accounting would show that it is always cheaper to build and launch a new thingy than to retrieve and relaunch one.

I am going to admire Kai saying “sizeable field of view” and “Hubble” in the same sentence (and have that sentence be correct!)