Ring-Mold Craters on Ceres: Evidence for Shallow Subsurface Water Ice Sources

Abstract

One of the main tasks of the Dawn mission is to characterize the potentially ice-rich crust of the dwarf planet Ceres. Ongoing studies reveal morphological features related to ice-rich material such as pits or particular landslides. Here we report the identification of ring-mold craters within the huge impact crater Occator. The Cerean ring-mold craters exhibit strong morphological similarities to the ring-mold craters on Mars, where ice-rich material is thought to be involved in such crater development. We discuss the occurrence of water ice reservoirs in the subsurface and assume that ice-rich material likely plays an important role in the development of ring-mold craters on Ceres. The occurrence of ring-mold craters on the surface of Ceres is not only a sign of water ice reservoirs in the subsurface but can also be used for the study of habitable zones on planetary bodies.