Rhea is the largest of Saturn's inner satellites with a diameter of 1530 km. Rhea orbits the planet once every 4.5 days. It is locked in its rotation with the same side always facing Saturn.

     Rhea has a density of 1.3, slightly less than Dione, and indicating it is composed of rocky material along with ice. Its forward facing hemisphere (in direction of orbital motion) is covered with nearly pure water ice. This forward hemisphere is further divided into two regions. One region contains all large craters, and the other half contains all small craters. There is also remains of 3 multi-ringed basins on this hemisphere. Also like Dione, Rhea has wispy areas on the trailing hemisphere that are believed to be fresh water ice.