On this day in 1789, William Herschel discovered Mimas, the seventh known satellite of Saturn. Herschel discovered Mimas only three weeks after discovering Enceladus, Saturn’s sixth-largest moon. He credits the discoveries to the development of his 40-foot telescope.
Because of its unique surface features, Mimas has been compared to the Death Star from the Star Wars films due to a large, prominent crater on its equator. Mimas has been visited by several spacecraft, including Pioneer 11, both Voyagers, and several visits by Cassini.