Let's use 4 x 8.2 meters for the NEO search
All this astrophysics is all very nice, but as I write there is a very large chunk of space junk with Earth's name on it headed our way. Why don't we find that thing first, and then do all this nice astrophysics?
The four 8.2 meter telescopes, operated separately, should be able to do a full sky search down to a good magnitude quite quickly, and then could repeat it at regular and frequent intervals, and then be returned to astrophysical duties.
Of course, this would be no substitute for the necessary space based assets, but it would help.
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