Saturn’s moon Dione harbors a subsurface ocean
http://www.astro.oma.be/en/saturns-moon-dione-harbors-a-subsurface-ocean/
A subsurface ocean lies deep within Saturn’s moon Dione, according to new data from the Cassini mission to Saturn. Two other moons of Saturn,
Titan and Enceladus, are already known to hide global oceans beneath their icy crusts, but a new study suggests an ocean exists on Dione as well.
In this study, researchers of the Royal Observatory of Belgium show gravity data from recent Cassini flybys can be explained if Dione’s crust floats
on an ocean located 100 kilometers below the surface. The ocean is several tens of kilometers deep and surrounds a large rocky core. Seen from within,
Dione is very similar to its smaller but more famous neighbor Enceladus, whose south polar region spurts huge jets of water vapor into space. Dione seems
to be quiet now, but its broken surface bears witness of a more tumultuous past. The study is published online this week in Geophysical Research Letters.