This image released by NASA on Thursday, March 22, 2012 shows the far side of the moon with Earth in the background. It was among more than 60 images taken by one of NASA's spacecraft in orbit around the moon. The cameras are operated by middle school students as part of a project. (AP Photo/NASA)
The surface of the moon
A surprising new view of the moon comes from detailed gravity mapping by twin spacecraft, which slipped into orbit around the celestial body earlier this year.