The rings appearance changes from year to year, as Saturn's orientation relative to the Earth changes in the course of its 29 year revolution around the Sun. The rings are not a solid, flat plane, but are composed of billions of separate particles of various sizes. The rings orbit each giant planet over its equator. Jupiter's rings are mostly dust particles caught in its gravity. The ring system itself is about 100 m thick.
Tidal Forces keep ring particles from forming moons.
Roche's Limit for any planet depends on the planet's density and the object's density, but is usually 2-3 planetary radii outward. Observations confirm that all ring systems are within Roche's Limit for their planet. Shepard moons keep rings orderly. Perhaps the particles were knocked off the surface of the planet's moons via impacts, or are a disrupted moon. As we discussed previously, some terrestrial planets lack atmospheres because they were too small .