Re: Is this a narrow minded view of the proposed Hubble Repair Mission?

Jan Vorbrüggen wrote:
Adaptive optics can only match *some* of HST's capabilities in the visible spectrum, and *none* of HST's capabilities in the ultraviolet or infrared.


...actually, make that infrared instead of visible. You can use a visible (Na+-line) artificial guide star, but the speed and size of the corrections of the wave front are fast and large enough for visible light. UV is of course a clear area where orbital images are the only game in town.

Terrestrial observations, even in the wavelengths where adaptive optics
works, also suffers from much larger background (from airglow). Adaptive
optics also only works over a very small patch of sky.

On the plus side, ground telescopes can have much larger apertures, so
they can collect many more photons.

Paul
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