Provocative title for this thread, huh? Anyway, I got to wondering if, when we get set up on the moon, we could conduct routine surveillance of Earth, 24/7/365. If so, we could tell when any spacecraft were approaching and even if they entered our atmosphere. Could this be set up practically?It seems like it might help in the argument over whether or not we are visited by alien beings. Whaddayathink?Daryl in Sagle, ID