Until recently the moon was taught to be bone dry, but researchers found the water on the moon comes in three different flavours. Mini-SAR found 40 craters, each containing frozen water at least 6.6 feet (2 meters) deep on the lunar surface – which adds up to 600 million tons of lunar ice stuff altogether. LCROSS slammed into the moon on Oct. 9, 2009 and found evidence of water in another crater.
Paul Spudis of the Lunar and Planetary Institute in Houston, Texas, said, “We have Mini-SAR’s thick lenses of nearly pure crater ice, LCROSS’s fluffy mix of ice crystals and dirt, and M-cube’s thin layer that comes and goes all across the surface of the moon. So far we’ve found three types of moon water.”
“It looks as though at least two different layers of our crater soil contain water, and they represent two different time epochs,” said Anthony Colaprete, LCROSS principal investigator. “The first layer, ejected in the first 2 seconds from the crater after impact, contains water and hydroxyl bound up in the minerals, and even tiny pieces of pure ice mixed in. This layer is a thin film and may be relatively ‘fresh,’ perhaps recently replenished.” It’s probably a sign that the moon water comes from more than one source.
“Some of the water may be made right there on the moon,” Spudis said. “Protons in the solar wind can make small amounts of water continuously on the lunar surface by interacting with metal oxides in the rocks. But some of the water is probably deposited on the moon from other places in the solar system.”