Thermal Stability of Water Ice in Ceres' Craters: The Case of Juling Crater

Abstract

Ice thermal stability on the surface of the dwarf planet Ceres is an important issue linked to the Herschel observations of water vapor around Ceres. One of these surficial ice deposits is located within the 20-km crater Juling (35°S, 168°E). The study of water ice exposure in this specific crater is particularly interesting because it has been observed that the water ice abundance changes on a time scale of a few months. To understand the ice behavior, we applied a 3-D finite element method thermophysical model to the study of Juling crater in order to determine the water ice sublimation rate. We use a detailed shape model of Ceres derived from optical imagery returned by the Framing Camera on board Dawn. We explore the effects of different heliocentric distances and different thermal inertia values, comparing our numerical predictions with the observational evidences returned by VIR and by the Herschel Space Observatory.