Moonday: Mimas

Phil Plait at Bad Astronomy posted this image last Wednesday, and I feel compelled to pass it along (full size here). That flat ding on the right of this moon is not an image artifact; it's the side view of an enormous crater.

Voyager 1 passed through the Saturn region in November of 1980, just three years after the first Star Wars film was released. Though Mimas had been discovered in 1789, the views sent back from that flyby immediately gave the moon it's nickname, the "Death Star moon." According to Wikipedia (which is also where the image below comes from), "The impact that made this crater must have nearly shattered Mimas: fractures can be seen on the opposite side of Mimas that may have been created by shock waves from the impact travelling through the moon's body." More information at the Wikipedia link and at the Bad Astronomy post.