China’s Chang’E-5 rover has found evidence of water molecules on the surface of the moon. Also, measurements taken by the rover indicate that the sun itself is the likely cause of the sparse yet detectable lunar water.
BACKGROUND: WATER ON THE MOON ONCE SEEMED UNLIKELY
Before humans first walked on the moon back in the 20th century, it was always assumed that the moon’s surface was completely dry. That conclusion was based on the fact that the moon has no atmosphere, and therefore seemed to lack the mechanisms needed to keep any water that might have previously been on the moon from evaporating into space.
That perception changed when a range of NASA missions including the Lunar Crater Observation and Sensing Satellite found evidence of water hiding in the permanently shadowed areas of certain lunar craters. Then, in 2020, NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) spotted water spread across the surface of the moon even in sunlit areas.
Now, the Chinese rover has been able to confirm those finding close up, while also shining some light on how exactly an atmosphere-less moon is gaining and maintaining water.
ANALYSIS: BEJING, WE HAVE FOUND WATER!
Published in the journal Science Advances, the researchers analyzing readings from the Chang’E-5 rover announced that “We estimate up to 120 parts per million (ppm) of water (OH + H2O) in the lunar regolith, which is mostly attributed to solar wind implantation.”
According to NASA, earth’s Sahara Desert has about 100 times this level of water density, so the water found by the Chinese team is a very small amount. Somewhat surprisingly, both NASA and the Chinese National Space Administration (CNSA) believe that the same reason they thought that the moon couldn’t have water may be the same reason it has water – the sun.
In 2020, NASA hypothesized “a two-step process whereby the Sun’s solar wind delivers hydrogen to the lunar surface and causes a chemical reaction with oxygen-bearing minerals in the soil to create hydroxyl. Meanwhile, radiation from the bombardment of micrometeorites could be transforming that hydroxyl into water.”
China’s newest readings seem to confirm that concept, with the researchers at the CNSA reporting that the water they found “is mostly attributed to solar wind implantation.”
The Debrief recently reported on how this type of solar wind may have been responsible for a significant amount of the water found on earth, as well as helping to make that water habitable.
Oddly, the Chang’E-5 rover did spot a slightly higher concentration in a surface rock named CE-5 rock, which “exhibits a stronger absorption, near 2.85 μm, than the surrounding regolith, with estimation of ~180 ppm of water.”
Compared to the overall surface readings at around 120 ppm, they think this rock may have been “transported from an older basalt unit,” and that the higher water content “may suggest an additional [water] source from the lunar interior,” meaning an underground source yet to be located.
OUTLOOK: MOON WATER WILL AID COLONIZATION
The detection of water on the moon is a significant step for those hunting for extraterrestrial life. But it is equally if not more important for human’s hoping to one day colonize out lone natural satellite, since water contains oxygen needed for breathing, as well as H2O being a necessary ingredient for growing food.
The Debrief recently reported on the methods engineers have outlined that will help these colonists extract both water and useable methane from the lunar regolith for such purposes. The Debrief also reported on how simulations show that these types of off-world colonists are likely to become more independent over time.
Bottom line, NASA’s 2020 finding of water on the moon’s surface has been confirmed by this latest Chinese finding, so whether it is used for fuel or as a means for colonial independence, this critical to life molecule will be part of any future human story taking place on the moon.
Follow and connect with author Christopher Plain on Twitter: @plain_fiction