Joe DeLuco asked:
I was wondering with all the maintenance that the Hubble telescope has shown to require why there isn't simply a telescope similar to it as part of the International Space Station?
Wouldn't it be easier to maintain and operate?
Dave - The simple answer is that there are people on the Space Station, and they are doing things! For instance, if you pushed off the inside of the space station to move yourself down, the Space Station is going to move up a bit. Tiny movements like this, even though people are very small compared to the weight of the space station, are more than enough to ruin your pictures.
So, if you want to make a good telescope, you want it to be as far away from anything else as possible. We don’t actually really want it in low Earth orbit at all, although the Hubble space telescope is, because heat from the nearby Earth can affect things. But you definitely don’t want any vibrations, so you want it away from any people, especially if they’re moving around. That's why they built their own satellite for the Hubble, independent of the space station.