Mystery of How the Moon Got Its Bull's-Eye May Be Solved

The crater in question, called the Orientale impact basin, is located on the edge of the moon's near side, so the feature is barely visible from Earth. To understand Orientale's rings, scientists needed to look deeper than the lunar surface and into the moon's interior structure. With the help of NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission, they did exactly that.