From PhysOrg:
Last fall, researchers, including Larry Taylor, a distinguished professor in the Department of Earth and Planetary Sciences, discovered “lunar dew” on the moon's surface — absorbed “water” in the uppermost layers of lunar soil. This discovery of water debunked beliefs held since the return of the first Apollo rocks that the moon was bone-dry. Now, scientists, including Taylor and Yang Liu, research assistant professor in the Department of Earth and Planetary Sciences, have discovered that water on the moon is more widespread — on the outside and inside of the moon — with some similarities to water in volcanic systems on Earth.
Their research will be featured in the article, “Lunar Apatite with Terrestrial Volatile Abundances” in the July 22 edition of the scientific journal, Nature. Unlike lunar dew which is believed to come from an outside source such as solar wind which brings hydrogen into contact with the Moon's oxygen, the water discovered by Taylor and Liu is internal, arising from an entirely different origin. How it got there is not yet known. The water may have been added by impacting comets, which contain ice, during or after the formation of the moon and Earth.
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