Composition, Structure, Dynamics, and Evolution of Saturn's Rings

Cassini observations confirm that Saturn's rings are predominantly water ice. The particles in Saturn's rings cover a range of sizes, from dust to small moons. Occultation results show the particles form temporary elongated aggregates tens of meters across. Some of the ring structure is created by moons, others by various instabilities. Data from future Cassini measurements can help investigators decide if the rings are remnants of the Saturn nebula or fragments of a destroyed moon or comet.