After discovering Pac-Man on the Death Star — aka Mimas — NASA has discovered a new Pac-Man in Tethys. And they still don't know why the hell this shape appears, but they have a theory.
Scientists theorize that the Pac-Man thermal shape on the Saturnian moons occurs because high-energy electrons bombard low latitudes on the side of the moon that faces forward as it orbits around Saturn, turning a fluffy surface into hard-packed ice. As a result, the altered surface does not heat as rapidly in the sunshine or cool down as quickly at night as the rest of the surface, similar to how a boardwalk at the beach feels cooler during the day but warmer at night than the nearby sand.
The most surprising thing about the Tethys Pac-Man is that it also appears on visible-light images, not only thermal analysis. I can't wait till the discover Mario jumping on Titan. [NASA]