China’s Lander Has Detected Water on the Moon

China’s Chang-5 lunar Lander has found evidence of hydroxyl (OH) on the Moon. Hydroxyl is a close chemical cousin of water, H2O. Several other orbital missions have detected OH on the Moon previously, Chang’e-5 marks the first time it has been detected by a spacecraft sitting on the lunar surface.

Chang’e-5 is most famous for its sample return mission, which brought a sample of lunar regolith back to Earth in December of 2020. However, for the detection of hydroxyl, the Chang’e-5 Lander used instruments on board to look at the area around the Lander site.

Scientists could use data from a panoramic camera, lunar mineralogical spectrometer (LMS), and lunar penetrating radar to look for evidence of water molecules. A rock near the Lander site contained the most hydroxyl, almost twice as much as the surrounding regolith. The regolith has less than 120 parts per million (ppm) of water molecules, while the rock has about 180 ppm.An international team of scientists led by researchers from the Chinese Academy of Sciences in Beijing published their paper in the journal Science Advances.

Water molecules were first detected on the Moon in 2009. In September of that year, scientists from three different space missions announced they had detected widespread water across the surface of the Moon.In November of 2009, the LCROSS science team held a press briefing to announce they had detected “buckets” of water inside the crater. The LCROSS impactor blasted material from inside Cabeus Crater, with a spacecraft making observations of the debris.