Saturn Rings 'Rev 173'NASA's Cassini mission recently captured these gorgeous views of Saturn's D ring and the inner C ring. In one image, the boundary between the bright and faint areas -- cutting approximately through the middle of the image -- is the boundary between the C (outer, brighter) and D (inner, fainter) rings. In another image, Cassini imaged only one bright feature of the faint D ring and the C ring does not appear.