Surface and subsurface regolith characterization of lunar south pole using chandrayaan-2 dual frequency synthetic aperture radar (DFSAR)

Abstract

Despite its proximity to Earth, vast regions of the Moon remain unexplored quantitatively, particularly the Permanently Shadowed Regions (PSRs) which are located at the poles. Identified by LRO Diviner as the coldest lunar locations (temperature reaching <110 K), these PSRs harbour potential volatiles such as water ice, ammonia, methane etc. implanted into the regolith by solar winds and meteorite impacts which are valuable for future robotic and manned missions (Sharma et al., 2023b), prompting a need for precise mapping of their distribution and abundance. This research focuses on the south polar region ‘Faustini Rim A’ located at the latitude of 87.30 S, which was chosen as one of the potential landing sites for upcoming Artemis III mission. Moreover, ensuring a successful lander touchdown necessitates the selection of a terrain devoid of rocks as well as detailed study of the physical and geotechnical properties of the surface to ensure towards building a sustainable permanent lunar base in future. Therefore, this study utilizes Chandrayaan-2’s Dual-frequency Synthetic Aperture Radar (DFSAR) fully polarimetric data acquired by simultaneous operation mode to perform a comparative analysis of the presence of different types of scatterers, volumetric rock abundance, dielectric constant as well as physical and geotechnical properties of the regolith at surface and subsurface levels.