“Water may be as plentiful in the moon’s interior as the Earth’s, a study of Apollo mission lunar rocks has revealed. Trapped water was found in tiny volcanic glass beads returned to Earth in 1972 by the final manned mission to the moon, Apollo 17. Analysis of the samples suggests there could be 100 times more water in the lunar mantle, the thick rock layer beneath the surface crust, than was previously thought. In fact, there could be as much water in the lunar mantle as in the Earth’s mantle. If this is the case, it challenges a long-held theory about the moon’s formation. Most experts believe a huge impact early in Earth’s history ejected material into space that became the moon.” Source