[geoschmo]

Although, if someone were to figure out a way to get to the moon with some people, they could make a potentially legitimate claim of sovereignty. The moon, or some portion of it would be then a new independant country. They'd have to be recognized of course by the nations of earth for it to mean anything. But I cannot as a private citizen of the US claim a part of the moon, because as Baron says, in effect that is saying the US has proxy control over that territory. And the US and other nations have signed treaties forbiding that.