A Son of the Rock

Another fantastic photo from Astronomy Picture of the Day (5/1/12) taken by the Cassini spacecraft.

This clearly shows that the moons orbit in the same plane as Saturn’s rings (whose shadows are cast on the main planet in the background.) In this view the two moons are 900,000 kiolmetres apart from each other, Dione nearer to Saturn, with the edge of the rings another 300,000 kilometres beyond Dione.

Also obvious is Titan’s atmosphere which makes its edges appear fuzzy.