The small category includes Phoebe, Hyperion, etc. The 6 large, icy moons contain Mimas, Enceladus, Tethys, Dione, Iapetus, and Rhea . It is the largest, airless satellite of the jewel planet. It is also smally comprised of rocky material that is found inside the core. If water could have existed on Rhea , it could not have been retained in its liquid form.
Ice water is seen mostly at the poles and inside ancient impact craters.
The surface of Rhea is densly cratered. This is mainly because Rhea has little no atmosphere to deflect incoming meteors,etc. These ancient impacts rippled through the ice during the creation of the moon or in its early years. On the larger, outer moons, the surface has not changed much since the beginning of the solar system. In contrast, the smaller moons have been through various changing periods.