Unfortunately, the Keck scopes can't look at one point in the sky for 30 hours straight. My understanding is that the strength of the Hubble was not its resolving power but it's light grasp from being able to focus for periods that the Earth's rotation would not allow ground-based telescopes to match.

I don't know that there's really a great hue-and-cry over the decommissioning of the Hubble per-se. There are twinges of nostalgia among its strongest supporters, and there is also the fact that it is maintainable, repairable, and upgradeable - aspects that I understand will be lost in the next generation of space-borne telescopes. I wonder what kind of media will be available the day after scientists announce that the Herschel telescope's mirror cracked during liftoff and the resulting images will only be useful for X and Y, not Z as orginally planned.

The only reason the Hubble is going is the price-tag you mentioned. In terms of capability, it is still an immensely useful instrument, and it could (theoretically) serve us for another few decades scanning the entire sky to the depth that it has, thus far, only examined small portions. Unfortunately, it does so at a cost that is, pardon the pun, astronomical.

Sincerely,
Derrick Baumer

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