Two planets may have crashed together recently, resulting in one planet that's weirdly hot for its size. The planet 2M1207B, 170 light years from Earth, is 1300 degrees Celsius, despite being smaller than Saturn, judging from its infrared radiation. Young planets are generally hotter than older planets, but such a small planet should have cooled off quickly. So University of Arizona astronomers claim another planet crashed head-on into it, and gave us this action-packed reconstruction. [New Scientist]