Today at a press conference at Google's Mountain View, California headquarters, the X Prize Foundation announced the 10 official competitors for its $30 million Google Lunar X Prize. It will not be an easy thing to win. To qualify, a team must land a privately funded spacecraft on the moon, rove at least 500 meters, and beam a particular set of video, pictures and data back to earth. Oh, and ideally it will do this within the next four years, because after December 31st 2012, the purse drops to $15 million.