RINGS

Hundreds of tiny ringlets—a few of them elliptical rather than circular—comprise the classic A-, B-, and C-Rings, once thought to be uniform disks of material. The F-Ring, which was first sighted by Pioneer 11 in 1979, was observed to be three separate, intertwined ringlets.

The existence of a D-Ring between the C-Ring and the planet has been confirmed by observations during Voyager 1’s passage through Saturn’s shadow. The tenuous E-Ring, previously observed from Earth only when Saturn’s rings could be viewed edge-on (every 15 years), has also been observed during shadow passage. At least one other ring has been found between the E- and F-Rings in Voyager images.

Long, radial, spoke-like features in the B-Ring were dark when viewed upon approach and bright when observed after encounter when the spacecraft looked back toward the planet and the Sun.