Chandrayaan-2 Orbiter Detects Subsurface Water Ice in Lunar South Pole Craters

Scientists from India's Physical Research Laboratory have identified strong evidence of subsurface water ice on the Moon using data from the Chandrayaan-2 mission. Published in npj Space Exploration, the study utilizes radar observations from the orbiter’s Dual Frequency Synthetic Aperture Radar (DFSAR) to analyze nine doubly shadowed craters near the lunar south pole. These regions, characterized by extreme cold temperatures reaching minus 248 degrees Celsius, act as natural freezers preserving ancient ice. The research team found that four of the nine craters exhibited radar signatures consistent with buried water ice, particularly within the Faustini crater. By combining high circular polarisation ratio values with low depolarisation signals, the researchers developed a refined method to distinguish ice from rocky terrain, resolving long-standing debates about lunar radar reflections. This discovery is pivotal for future human exploration, as lunar water can be converted into drinking water, oxygen, and rocket fuel. The findings highlight the uneven distribution of ice deposits, offering crucial insights for selecting landing sites in the ongoing international race to explore the lunar south pole involving NASA, China, and India.