It's been almost four decades since astronauts last walked on the Moon. Yet the scientific bounty they brought back to Earth continues to yield discoveries about our satellite world. One example: the Moon may contain enough water to cover its entire surface to a depth of a few feet.
Evidence for lunar water has been building since the mid 1990s. Orbiting spacecraft have "sniffed" traces of water ice buried in craters at the Moon's poles. Craft have slammed into some of these craters, splashing bits of ice into the sky. And another craft found water mixed with the soil all across the Moon.
But a recent study of moonrocks here on Earth found that there could be a lot more water than the spacecraft have detected.
The study was led by Francis McCubbin of the Carnegie Institution, and looked at rocks from Apollo 14 and 15, as well as a lunar meteorite. The study team analyzed the rocks with techniques that hadn't been developed at the time of the Apollo missions.
The analysis showed that the rocks contain a mineral that's rich in a form of water. The amount of water in the samples suggests that the Moon could have a hundred times more water than scientists had thought -- enough to fill the lunar "seas" with real water.
You can see some of the lunar seas tonight -- seas of volcanic rock that form the dark spots on the surface. The full Moon climbs into view in early evening, with the bright planet Jupiter to its right.
Script by Damond Benningfield, Copyright 2010
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