Multidisciplinary Analysis of the Nippur Sulcus Region on Ganymede

摘要

On Jupiter's largest moon Ganymede, we focus on the southern region of Nippur Sulcus, including the Epigeus palimpsest crater. This region displays geologically recent terrains and has good coverage of optical and near infrared remote sensing data, primarily returned by the NASA Galileo mission. We first use high-resolution optical imagery to carry out a detailed geological mapping. We combine hyperspectral data to infer the surface composition of this area. We then apply two theoretical models. The first is a self-similar clustering that uses the mapping of the grooves present in this region to infer the thickness of the ice shell. A second model is used to estimate the radar clutter noise induced by the estimated local topography, which is key for constraining future radar measurements. Based on all findings, we provide a possible evolutionary history of the Nippur Sulcus and Epigeus areas. This exercise shows the potential of an interdisciplinary data analysis combining wide-ranging scientific objectives such as geology, surface composition, and geophysics in view of the future close exploration that will be conducted on Ganymede by the JUICE spacecraft. Our work combines multiple analysis techniques that could be applied to other regions of interest and will prove crucial when JUICE data become available.