Actually, it is not the atmosphere that blocks radiation, it is the gravitational field that blocks it. Say a blast of radiation comes from the sun, our field just reflects it. Also the moon does of a very, very thin atmosphere. The American flag turned white because the Moon's gravitational fields are very weak.

Sorry, we can't do anything. Hate to break your bubble, but the Moon is also moving away from us. To make you a new bubble, all this will happen long after our lives. Enjoy the Moon while you can! ^_^