Surface Composition of Mercury from NIR (0.7-4.2 μm) Ground-Based IRTF/SpeX Spectroscopy

Kurzfassung

On December 16-18, 2018,we obtained global disk-resolved NIR spectroscopic data of Mercury at the Infrared Telescope Facility (IRTF) on Mauna Kea, HI, using the SpeX 0.7-5.3 µm Medium-Resolution Spectrograph and Imager. During the observation, Mercury was ~63-70% illuminated. We observed geochemical terrains including high-Mg regions (HMR) where the largest abundances of Ca and S are found (HMR-CaS), northern volcanic plains (NVP), and intermediate terrain (IT) in the spectral region spanning 0.6–4.2 µm. These observations will not only yield new information of the surface mineralogy of Mercury for different geochemical terrains but will also help improve our preparations and planning for BepiColombo data acquisition and science for both spectroscopy and thermal inertia studies.