NASA scientists observe water molecules hopping about on the surface of the moon

Using NASA’s Lunar Reconnaissance Orbiter (LRO), scientists have observed water molecules dancing on the surface of the moon, on its dayside. This is big for two reasons. First, this is the first time an orbiting spacecraft has been used to so closely observe the movement of water molecules on the surface of a body like a moon, and second, the data could give us an idea about the quantity and distribution of water on the moon.As observed by the LAMP (Lyman Alpha Mapping Project) instrument aboard the LRO, water molecules leave the regolith (lunar soil) during the day and “hop around” the surface. Some even ascend into the atmosphere before settling back down. To be clear, these are water molecules we’re talking about, not droplets.Detecting water from orbit is especially challenging because instruments would have to detect a layer that is mere molecules thick. The moon’s surface is also very reflective, which further messes with the data. While it's been about 10 years since scientists confirmed that there is water in the Moon’s regolith, scientists couldn’t explain the distribution of that water and why its location appeared to change.[caption id="attachment_6235811" align="alignnone" width="1280"]

The LRO captured this stunning image of the Moon's Tycho Central Peak in 2011.[/caption]It was originally hypothesised that solar winds deposited hydrogen ions on the lunar surface. These could, in theory, result in the formation of water molecules. However, this theory would only hold true if water deposits decreased when the moon was shielded by the Earth, which was never the case. Water would be deposited regardless. LAMP’s latest observations have finally provided an explanation.According to Dr Kurt Retherford, a scientist working on the project, the findings are important given the country’s (the US) renewed focus on lunar exploration. An understanding of the lunar water cycle will also help us understand the accessibility of water, notes Amanda Hendrix, a senior scientist.The LRO was launched aboard an Atlas V rocket in 2009 and has spent the intervening years providing invaluable data on the moon.