Water on the Moon
A team of researchers discovered evidence of water on the moon. A new type of chemical analysis spotted signs of water molecules inside tiny beads of volcanic glass brought to Earth decades ago by the Apollo astronauts. The find may force astronomers to rethink their theories of how the moon formed.
Soon after it coalesced, Earth took at hit from a Mars-sized object. The resulting cloud of debris eventually condensed to form the moon-or so the thinking goes. But if the moon came from Earth, and Earth is mainly water, where is the lunar water?
Many planetary scientists think water blown away from Earth by the impact was instantly vaporized by the high temperatures of the collision. Others, have over the years, scanned these tiny glass beads-brought back by the Apollo missions. However, they found no water.
A team led by geochemist Alberto Saal of Brown University decided to use a more sensitive method. The secondary ion mass spectrometry technique detects trace amounts of volatile gases such as chlorine and fluorine in Earth soil samples. Applying it to lunar samples, the team has found trace amounts of water.
Saal declines to speculate about how much water the moon contains. Extrapolating the results to estimate the amount of lunar water would be like predicting "the final score of the game after we saw the first touchdown," he says. Meanwhile, he and his team will be studying as many lunar glass beads as possible to refine their analysis.