Here is a Cassini site
http://ciclops.org/view_event.php?id=58 featuring a bunch of images and short movies what Cassini imaged this last year. Very cool and informative. Some of these I have seen on " Astronomy Picture of the Day"
http://antwrp.gsfc.nasa.gov/apod/. At the bottom are up-to-date maps of some of the moons of Saturn. These could be incorporated into Celestia.
Don
