The moon isn't the dry dull place it seems. Traces of water lurk in the dirt unseen.
Three different space probes found the chemical signature of water all over the moon's surface, surprising the scientists who at first doubted the unexpected measurement until it was confirmed independently and repeatedly.
It's not enough moisture to foster homegrown life on the moon. But if processed in mass quantities, it might provide resources – drinking water and rocket fuel – for future moon-dwellers, scientists say. The water comes and goes during the lunar day.
It's not a lot of water. If you took a two-liter soda bottle of lunar dirt, there would probably be a medicine dropperful of water in it, said University of Maryland astronomer Jessica Sunshine, one of the scientists who discovered the water. Another way to think of it is if you want a drink of water, it would take a baseball diamond's worth of dirt, said team leader Carle Pieters of Brown University.
"It's sort of just sticking on the surface," Sunshine said. "We always think of the moon as dead and this is sort of a dynamic process that's going on."