Moon’s Hidden Ice Revealed: Chandrayaan‑2 Uncovers Subsurface Water at Lunar South Pole

India’s Chandrayaan-2 orbiter has uncovered strong evidence of buried water-ice beneath the Moon’s south polar craters, particularly inside the 1.1 km-wide Faustini crater. Using its Dual Frequency Synthetic Aperture Radar (DFSAR), the mission analyzed permanently shadowed regions (PSRs) where temperatures reach -248°C, preserving ice for billions of years. The radar’s polarimetric analysis revealed key signatures—Circular Polarization Ratio (CPR > 1) and Degree of Polarization (DOP < 0.13)—consistent with subsurface ice deposits. The DFSAR operates in L- and S-band frequencies, penetrating up to 2 meters below the lunar surface, making it the first fully polarimetric radar system to study the Moon. Scientists focused on ‘doubly shadowed craters,’ areas within larger PSRs that never receive sunlight, where ice could remain stable indefinitely. The strongest ice signal was detected in Faustini crater, whose lobate-rim morphology suggests an impact event exposed subsurface ice. This discovery holds significant implications for future lunar missions, including NASA’s Artemis program, as water-ice could serve as a critical resource for drinking water, oxygen production, and rocket fuel. For India, the findings further solidify its position in global lunar exploration, complementing the success of Chandrayaan-3 and aligning with its Space Vision 2047 roadmap. Challenges remain, however, including the extreme cold of the region, the buried nature of the ice, and the need for direct sampling to verify the deposits. Future missions will need to develop technologies capable of operating in such harsh conditions and accessing the ice deposits trapped beneath the lunar surface.