Saturn's A Ring. The NASA/ESA/Italian Space Agency Cassini-Huygens probe is providing fine views of Saturn. Here is the outer part of the ring, and ring's shadow projecting unto Saturn's northern hemisphere. As most of the ring is about 650 feet (200 m) thick, the A ring is just 160 ft thick (50 m). The Cassini Division -with ringlets inside- is at the bottom of the picture as the Encke Gap is seen at the upper part of the ring. Several fine ridges are visible along the A ring. The darker portion of the projected shadow (top right) is the B ring as the several lines seen on a lighter blue are part of the inner C ring (or crepe ring). The A ring is about 7,500-mile- (12, 000 km) wide as the outer F ring is seen like a thin blue streak. Ring's plane is seen from below. Saturn's ring is believed now to be young -a few hundred million years old only- and the result of a moon blasted off by an impactor, or of a celestial body ventured too close to the planet and ripped apart by tidal forces. In both case the debris collected into the planet's equatorial plane. All rings seen at gas giants are part of the same process. Rings at other planets like Jupiter, Uranus and Neptune are far much fainter than Saturn's. picture courtesy NASAJPL/Space Science Institute