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NASA announced today the discovery of water molecules inside a sunlit crater on the surface of the moon. The finding could have implications for future astronauts, as NPR's Geoff Brumfiel reports.
GEOFF BRUMFIEL, BYLINE: Astronauts who landed on the moon in the 1960s reported a wasteland.
CARLE PIETERS: When the Apollo samples came back, it was noticed they were very dry, very old. And that sort of set the stage.
BRUMFIEL: Carle Pieters is a professor emeritus at Brown University who's worked on the moon for decades. The rock samples showed at least where the astronauts had landed...
PIETERS: The moon was one of the driest places in the solar system.
BRUMFIEL: That story has changed in recent decades. More recent robotic missions have found water at the poles of the moon, buried in dark craters where the sun can't vaporize it. Now, even more surprisingly, researchers have found water in a sunny spot as well.
CASEY HONNIBALL: This is not puddles of water but instead water molecules that are so spread apart that they do not form ice or liquid water.
BRUMFIEL: Casey Honniball is a lead researcher on the study, which appears in Nature Astronomy. Honniball and her colleagues found the water inside Clavius crater, one of the largest visible from Earth. The water molecules may be trapped in microscopic glass beads or suspended in the lunar soil. However it got there, it does add up.
HONNIBALL: The amount of water is roughly equivalent to a 12-ounce bottle of water within a cubic meter of lunar soil.
BRUMFIEL: Future visitors would like to use this water. Jacob Bleacher is NASA's chief exploration scientist.
JACOB BLEACHER: Water is heavy. Anytime we don't need to pack water for our trip, we have an opportunity to take other useful items with us.
BRUMFIEL: Carle Pieters says the finding is scientifically interesting...
PIETERS: It's a lot in that it's a lot more than zero.
BRUMFIEL: ...But she isn't sure how useful it will be.
PIETERS: The question is, OK, how hard is it to extract it? How hard is it - once you've extracted it, do you just have to go on to the next site and do the same thing, or will it reconstitute itself? We don't know.
BRUMFIEL: NASA hopes to get a closer look. It's planning on sending a rover to the moon to drill for water directly.
Geoff Brumfiel, NPR News. Transcript provided by NPR, Copyright NPR.