Slashdot Mirror
Rotating Mercury Lunar Observatory
Fraser Cain writes "Universe Today is reporting on a proposal under consideration by NASA from Dr. Robert Angel at the University of Arizona. He wants to build a 100-meter liquid mirror telescope into a crater on the Moon. It would only be able to look at a specific spot in the sky, but the view would bury Hubble's Deep Field Survey." The challenges of off-Earth construction are left as an exercise for the reader.
Even if they could keep it clean during construction, how would they keep it from getting contaminated with lighter-than-mercury space dust over time?
The moon's atmosphere is basically hard vacuum. Sure, there are a few air molecules here and there, but certainly nothing that could lift and transport dust particles.
So, short of nearby meteorite impacts kicking up dust and micrometeorites falling to the surface, there really isn't any way for dust to get on the mirror in the first place. And keep in mind that even such dust as would be sent up by the occasional meteorite wouldn't hang around in the air the way it would on Earth, because there isn't any air. It would just trace a parabolic arc and fall straight back down (well, it wouldn't be quite that simple due to the the gases released by the meteorite's own impact, but you get the point).
I very much doubt that the minute quantities of dust that would find their way onto the mirror would present a significant problem.
ZFS: because love is never having to say fsck
First off, this far outstrips our present launch capability. Second, we would require a much more reliable method of sending things into space before we decided to send up a significant amount of liquid mercury, given that a failed launch of a rocket carrying a large tank of mercury would be a major ecological disaster. It's a great idea in theory- pouring a bunch of liquid into a bowl would be certainly preferable to the tremendous amount of skill and effort required to properly build and polish large telescope mirrors- but I'm not sure how long it would be before this idea becomes even remotely practical.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
Has any one though of starting with a spinning liquid mecury mirror, letting it freeze, and then using it as a conventional telescope mirror. You could even remelt and respin it should it become contaminated. More complicated yes, but also more useful....