You might not realize it, but water is a lot more common on the moon than you probably think—albeit not in its liquid form. Instead, water shows up as ice all over the lunar surface. While it’s not as prevalent as our own wet planet, lunar water has the potential to be a very valuable resource for future lunar colonies—so as long as we know where to look for it.
Researchers in China have discovered evidence of a surprising location for moon water: glass beads. In a study published Monday in the journal Nature Geoscience, scientists analyzed lunar samples collected by China’s Chang’e-5 mission and brought back to Earth. They found that glass beads formed by impacts from space rocks can store water, suggesting that the moon and other “airless bodies” like asteroids might actually have more water on their surfaces than expected.
Surprisingly, the water might be coming from a very unexpected source: the sun. As solar winds pummel the lunar surface with protons, these molecules interact with the oxide within the minerals. Over time, this can create hydrogen and, therefore, the ingredients for water.
“Our direct measurements of this surface reservoir of lunar water show that impact glass beads can store substantial quantities of solar wind-derived water on the moon and suggest that impact glass may be water reservoirs on other airless bodies,” the authors wrote.
To reach their findings, the researchers analyzed the water content of glass beads extracted from Chang’e-5’s lunar soil samples. They discovered that the glass beads could gather water over the course of just a few years and then be released back into the moon’s thin atmosphere. This creates an active water cycle on the moon—albeit one that’s much different than the one on Earth.
The findings also indicate that impact glass could hold water for other airless bodies in space. “Asteroid and comet impacts are the major exogenous processes that reshape the surface morphologies of airless bodies, as evidenced by the widespread presence of impact craters on the moon, Mercury, and asteroids,” the authors wrote.
The authors also note that the glass beads could be an incredibly valuable resource for astronauts on the lunar surface. Not only could they potentially drink the water, but water could also be used to make sustainable rocket fuel. This may drastically cut down the costs for future moon colonization efforts.