In October, NASA crashed a two-ton rocket and the SUV-size LCROSS (Lunar Crater Observation and Sensing Satellite) into the permanently shadowed crater Cabeus on the moon's south pole.
Despite disappointing many amateur astronomers on Earth, who had been expecting to see a giant plume of lunar dust and ice crystals, the moon-water mission was a success, NASA says, National Geographic News reports.
"We found water. And we didn't find just a little bit. We found a significant amount," Anthony Colaprete, lead scientist for the mission, told reporters as he held up a white water bucket for emphasis.
He said the 25 gallons of water the lunar crash kicked up was only what scientists could see from the plumes of the impact.
Some space policy experts say that makes the moon attractive for exploration again. Having an abundance of water would make it easier to set up a base camp for astronauts, supplying drinking water and a key ingredient for rocket fuel.
"Having definitive evidence that there is substantial water is a significant step forward in making the moon an interesting place to go," said George Washington University space policy scholar John Logsdon, The Associated Press reports.
Michael Wargo, chief lunar scientist at NASA headquarters in Washington, said the discovery holds promise for future exploration. Using solar energy, future astronauts could, in theory, break down recovered ice and in effect live off the land.
"Water can be used for the kind of things we think about every day, drinking water if we have extended crews on the surface," he said. "You can break it down and have breathable air for crews to breathe. But also, if you have significant quantities of this stuff, water really is the constituents of one of the most potent rocket fuels: oxygen and hydrogen."
Whether the water ice detected by LCROSS might be accessible to future astronauts remains to be seen. But scientists were elated with the initial findings.
The $79 million LCROSS mission was launched June 18 as a companion payload to NASA's $504 million Lunar Reconnaissance Orbiter spacecraft. Working in a 31-mile-high orbit, LRO is designed to create a high-resolution map of the moon's surface to help identify sites for future manned missions, CNET News informs.