There might be less water on the moon than we'd hoped

"Analyzing images of the moon's darkest areas from ShadowCam, a NASA instrument on the Korea Pathfinder Lunar Orbiter, the study's authors determined that, in most of the moon's darkest craters, water makes up less than about 20 to 30 percent of the material by weight—and that many may have no surface ice at all."

"The multibillion-dollar question remains just how abundant that ice is—and thus how much future explorers might rely on it for producing potable water, manufacturing rocket fuel or merely studying its composition to better determine how it fits into the bigger picture of H2O."

"Hints of a potentially revolutionary breakthrough emerged in the 1990s, when a U.S. spacecraft, Clementine, spied tentative signs of water ice at the floors of craters called permanently shadowed regions (PSRs) around the lunar south pole."

Apollo 11 astronauts initially concluded the moon was completely dry based on returned samples, but decades of research revealed traces of water in lunar materials. In the 1990s, spacecraft detected potential water ice in permanently shadowed regions (PSRs) around the lunar south pole. Evidence for lunar water accumulated over years, yet scientists struggled to quantify its abundance. A recent study analyzing ShadowCam imagery from the Korea Pathfinder Lunar Orbiter determined that water comprises less than 20-30 percent of material by weight in most of the moon's darkest craters, with many possibly containing no surface ice. The precise quantity of lunar ice remains crucial for determining its utility for future exploration, including water production, rocket fuel manufacturing, and scientific study.

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