Cassini is not the only satellite studying the Saturn system
Saturn's Rings Sparkle with X-rays
Chandra images reveal that the rings of Saturn sparkle in X-rays.
The likely source for this radiation is the fluorescence caused by solar
X-rays striking oxygen atoms in the water molecules that comprise
most of the icy rings.
< http://chandra.harvard.edu/photo/2005/saturn_rngs/ >