Understanding the presence of water on the Moon is crucial for future missions and for comprehending the formation and evolution of our satellite. A team of researchers from the University of Hawaii has discovered that high-energy electrons in Earth’s plasma sheet could be influencing the processes of lunar erosion and playing a fundamental role in the formation of water on the Moon.

According to experts, the high-energy electrons present in Earth’s plasma tail may be responsible for lunar erosion and the formation of water on its surface. This discovery could also explain how water accumulates in permanently shadowed regions of the Moon, where sunlight never reaches.

Earth’s magnetosphere protects it from solar radiation and space erosion. High-energy electrons and ions form an extended magnetic tail due to solar wind. The Moon, in turn, spends about 27% of its journey within this magnetic tail during its monthly orbit around Earth. It was during this period that the team of scientists focused on studying the processes of water formation on the lunar surface.

The researchers analyzed data collected by India’s Chandrayaan-1 mission between 2008 and 2009. These data revealed that water formation in Earth’s magnetic tail is similar to the periods when the Moon was outside of this region. This indicates that there may be additional formation processes or new sources of water not directly associated with solar wind.

High-energy electrons could be interacting with the lunar soil, releasing trapped hydrogen that can then combine to form water. These findings suggest that Earth and the Moon are closely linked in various aspects that had not been recognized before. The team of researchers plans to continue studying the plasma environment around the Moon and the water content at the lunar poles as part of NASA’s Artemis program.

Source: S. Li et al. Formation of lunar surface water associated with high-energy electrons in Earth’s magnetotail. Nature Astronomy, published on September 14, 2023; doi: 10.1038/s41550-023-02081-y.