Mimas was nearly destroyed by something still unknown. It left one of the largest craters on Saturn’s smallest moon, making it look like Star Wars Death Star. The crater is named Herschel, after Sir William Herschel who discovered it in 1789. It’s referred to as a big dirty snowball because it’s made mostly of water ice with scattered rock. Mimas also has an unusual wobble which is believed to be caused by having a liquid water interior.
The photo was taken by the spacecraft Cassini while in Saturn’s Orbit in February 2010.