Researchers have continuously speculated that the Moon might harbor traces of water ice, but new observations conducted with NASA’s Moon Mineralogy Mapper (M3) instrument on the Chandrayaan-1 spacecraft definitively confirm the longstanding idea.
The findings, which have been published in the Proceedings of the National Academy of Sciences this week, divulge how the Moon contains perceptible amounts of water ice in what some might consider predictable places.
Image Credit: NASA
As it would seem, the M3 instrument detected three distinctive signatures that scientists often look for when searching for water ice on other worlds. Among those, the water ice’s reflectivity was spot-on, and it seemed to absorb infrared light in a particular manner.
Most of the water ice patches discerned by the M3 instrument inhabited the shadowy confines of craters at the Moon’s North and South poles. These regions never see the light of day due to the Moon’s tilt, enabling them to stay cold enough (around -250º Fahrenheit) to sustain their water ice caches.
While previous studies have indirectly detected water ice on the lunar surface via a single signature, this study is particularly fascinating because it’s one of the first to confirm it with several signatures.
That said, the study officially lays the conjecture to rest, but it also raises further questions. For example, if water ice can exist within the Moon’s frostiest surface cavities, then could it also live beneath the surface?
It’s a good question, albeit more challenging to answer without physically visiting the Moon and doing a bit of digging. Fortunately, the presence of water ice on the lunar surface means that long-term lunar missions might not be too far out of reach.