A NEW analysis of volcanic glass recovered from the moon decades ago has found the rocks contain traces of the constituents of water, challenging a long-held notion that the moon is perfectly dry.
Using a technique not available when Apollo astronauts collected the rocks in the 1970s, scientists detected tell-tale signs of water trapped inside the pebble-like glass. The discovery suggests water was present on the moon between 3.3 billion and 3.6 billion years ago, when the pebbles formed during lunar eruptions.
The report, published yesterday in the journal Nature, may cause scientists to rethink theories on how the moon was formed.
The finding throws at least a little water on the currently favoured hypothesis for the moon's origin. Many scientists think it was formed when a large proto-planet slammed into Earth, sending molten debris off into space that eventually became the moon. Scientists have long assumed that the heat of the collision would have vaporised any water present, and that the gravitational pull of the primeval moon would not have been enough to recapture the water vapour.