Rotationally-resolved spectra of Ceres in the 3-μm region

Abstract

Abstract We present observations of Ceres over the 2.2–4.0 μm region taken using the SpeX instrument on the NASA IRTF in 2005. The observations cover Ceres’ entire longitude range and show evidence for a relatively uniform surface in terms of Ceres’ composition, however there is a subtle but consistently shallower band depth over longitudes associated with bright regions in HST maps, suggesting those areas are slightly less carbonate- and brucite-rich. We also find Ceres’ beaming parameter, a measure of its thermal properties, to have changed with its viewing aspect.