NASA's probe MESSENGER flew by Mercury a couple of weeks ago, and the photos have started pouring in. This is one of the most striking. Nicknamed "the spider," it's probably the result of a meteor impact with about fifty cracks radiating outward from it. Apparently, it's the only such structure in the solar system, making it officially cool.

[Special note to Moff and Blakeley: Just try making dick jokes about this picture! It can't be done!] Image courtesy of NASA/JHUAPL/CIW NASA Spots Mystery Spider Scar [Space.com]