The interior of the moon contained water early in its history, suggesting the formation theories of the moon may have to be re-thought, U.S. researchers say.
University of Michigan researchers and colleagues found tiny amounts of water in mineral grains from samples from the lunar highlands obtained during the Apollo missions.
The lunar highlands are thought to represent the original crust that crystallized from a mostly molten early moon, suggesting the lunar interior contained water during this molten stage before the crust solidified, a university release said Monday.
That's difficult to reconcile with the theory that the moon formed from the debris generated during a giant impact with the proto-Earth and any water in lunar rocks was added after its formation by smaller meteorite impacts or solar wind.