[gwd]

<pedantic> adverb </pedantic>

The other thing to remember was that Hubble was designed in an era that the Space Shuttle was meant to make manned missions to repair / upgrade commonplace. My understanding is that this was actually done at least once to Hubble (maybe more? I forget); but unfortunately for Reasons, NASA turned out to be incapable of resisting cutting corners which put people's lives at risk (Challenger, Colombia). A system designed today would be designed assuming that it would be robots or nothing.

[mannykannot]

I was curious myself, and it turns out there were five missions, starting with the one to compensate for the incorrectly ground mirror. IIRC the final one was in doubt, as there was no possibility of a rescue mission in the event of irreparable damage on launch.

https://www.nasa.gov/mission_pages/hubble/servicing/index.ht...

[DylanSp]

The final servicing mission (STS-125) ended up with a contingency plan for damage on launch, STS-400. Another shuttle was prepped and on the pad for a rescue mission if the primary shuttle was damaged.