14 March 2008
Just as I thought Saturn’s little ice moon Enceladus couldn’t get any cuter, I found out it has dimples. You won’t spot them easily in the Cassini images, but in topographic maps, which Dr. Paul Schenk presented yesterday at LPSC, they’re striking. Schenk identified 5 large depressions smattered across Enceladus, each roughly 100 km across and 1 km deep. For a moon the size of Great Britain, those dimples are big. They’re different than the famous depression at the South Pole (where the moon’s plumes originate) – they’re about half as wide, but twice as deep. While Schenk doesn’t yet have a good explanation for how they formed, he noted that they appear to be superimposed on the geology, and that could put some constraints on when they formed.
So far, Schenk’s maps only cover about half of Enceladus – stay tuned in the next months as Cassini looks for dimples on the other side.