Global Spectral Properties and Lithology of Mercury: The Example of the Shakespeare (H-03) Quadrangle

Abstract

The MErcury Surface, Space ENvironment, GEochemistry and Ranging mission showed the surface of Mercury with an accuracy never reached before. The morphological and spectral analyses performed thanks to the data collected between 2008 and 2015 revealed that the Mercurian surface differs from the surface of the Moon, although they look visually very similar. The surface of Mercury is characterized by a high morphological and spectral variability, suggesting that its stratigraphy is also heterogeneous. Here, we focused on the Shakespeare (H-03) quadrangle, which is located in the northern hemisphere of Mercury. We produced an 8-color cube of this quadrangle at 450-m per pixel spatial resolution and with a complete coverage. Various selected color maps based on this eight-color cube were used to analyze the spectral properties of this region to define its compositional variability and identify some clear units constrained by relevant spectral parameters: for example, we identified a higher concentration of low reflectance material around three main craters of Shakespeare (Degas, Akutagawa, and Sholem Aleichem) and in the area to the south of Sobkou Planitia delimited by 24.4°N to 28.4°N and -140°W to -125°W. Moreover, we selected some regions of interest, which can be proposed as particularly interesting targets for the Visual and Infrared Hyper-spectral Imager and Mercury Radiometer and Thermal Imaging Spectrometer instruments onboard the BepiColombo spacecraft. This work can help for the geological analysis of this quadrangle, by integrating information that are usually not derived with a single morphostratigraphic analysis.