Chinese scientists find ‘lunar water’ in soil samples brought by Chang’e-5 from Moon for the first time

Chinese scientists have made a groundbreaking discovery of water molecules in lunar soil, a finding that could significantly enhance our understanding of the Moon’s evolution.

This discovery was based on studies conducted on lunar soil samples brought back by China’s Chang’e-5 mission in 2020, and it challenges the longstanding notion that the Moon is completely dry, and that water is present only in ice form.

Decades ago, American Apollo astronauts brought back lunar samples that showed no signs of water, leading scientists to conclude that the lunar soil was entirely dry. This conclusion was supported by NASA, which asserted that the Moon’s surface lacked water. However, advances in technology and further explorations have slowly begun to challenge this notion.

In 2009, India’s Chandrayaan-1 spacecraft detected signs of hydrated minerals, indicating the presence of water molecules in sunlit areas of the Moon. This was a significant step forward, but it wasn’t until 2020 that NASA announced the discovery of water on the Moon’s sunlit surface using data from the Stratospheric Observatory for Infrared Astronomy (SOFIA). These findings were primarily based on remote sensing and microanalysis techniques, which suggested that water could exist in the form of hydrogen and oxygen molecules.

The Chang’e-5 mission, which retrieved lunar samples from the Moon’s near side in 2020, has provided a fresh opportunity to investigate the presence of water. These samples were younger and from a higher latitude than those collected by previous Apollo and Soviet Luna missions. The research, carried out by scientists from the Beijing National Laboratory for Condensed Matter Physics and the Institute of Physics of the Chinese Academy of Sciences (CAS), was published in the journal Nature Astronomy on July 16.

Using a sample provided by the China National Space Administration, researchers isolated over 1,000 mineral clasts. Among these was a plate-like transparent crystal, named “unknown lunar mineral” (ULM-1), which contained water molecules. The team ruled out contamination from terrestrial sources or rocket exhaust, suggesting the water-bearing mineral originated on the Moon.

This discovery is significant because it provides direct evidence of water molecules in lunar soil, contradicting earlier conclusions of a dry Moon devoid of liquid water. The presence of water in lunar soil has massive implications for future lunar exploration and potential resource utilization.

The Chang’e-5 mission’s findings, along with previous discoveries by Chandrayaan-1 and NASA’s SOFIA, contribute to a growing body of evidence that water is present on the Moon.

China’s Chang’e-6 mission, which returned with up to 2kg of soil and rock samples from the Moon’s far side earlier in June of 2024, is expected to provide further insights. These samples, collected from one of the Moon’s oldest basins, will help researchers continue to unravel lunar mysteries, including the presence and distribution of water.

In summary, the discovery of water molecules in lunar soil by Chinese scientists marks a significant milestone in lunar research. It not only challenges the long-held belief of a dry Moon but also opens up new possibilities for future lunar exploration and resource utilization. As more missions return with lunar samples, our understanding of the Moon’s water content and its implications for space exploration will continue to evolve.