Operational insights and measurements of ChaSTE on the Chandrayaan 3 Vikram Lander

Abstract

Understanding the thermal properties of lunar regolith is crucial for accurately modelling heat transfer processes, evaluating the thermal behavior of lunar surface and subsurface, predicting volatile escape processes, and planning future exploration missions. Chandra’s Surface Thermophysical Experiment (ChaSTE) is a payload onboard Chandrayaan 3 lander of Indian Space Research Organisation (ISRO), which measured temperature and thermal conductivity of lunar regolith by inserting a thermal probe into the regolith. This study details the timeline of ChaSTE activities on the lunar surface, the penetration operation of the ChaSTE probe into the regolith, and measurements of thermophysical properties such as packing density and thermal conductivity and temperature up to a depth of $\sim$10 cm at the landing location (69.37 ° S, 32.32 ° E) on the southern high-latitude region of the Moon. The mission life of ChaSTE was $\sim$12 days during August – September, 2023. The measurements performed by ChaSTE are the first of their kind on the high-latitude lunar regolith.