This color-enhanced view of Mimas from NASA shows a bluish band around the equator. Experts are unsure of the nature of this blue band, though NASA speculates it could have something to do with the high-energy electrons that drift in an opposite direction to the flow of plasma in the magnetic bubble around Saturn. As NASA reports, Mimas is named for a giant who was killed by Mars in the war between the Titans and the gods of Olympus. It is the smallest and innermost of Saturn's major moons. Some note that its giant impact crater makes it similar to the Death Star featured in the "Star Wars" series.