ChaSTE (Chandra's Surface Thermophysical Experiment) measures the temperature profile of the lunar topsoil around the pole, to understand the thermal behaviour of the moon's surface. It has a temperature probe equipped with a controlled penetration mechanism capable of reaching a depth of 10 cm beneath the surface. The probe is fitted with 10 individual temperature sensors.

The presented graph (above) illustrates the temperature variations of the lunar surface/near-surface at various depths, as recorded during the probe's penetration. This is the first such profile for the lunar south pole. Detailed observations are underway.

The payload is developed by a team led by the Space Physics Laboratory (SPL), VSSC in collaboration with Physical Research Laboratory, Ahmedabad.