It is not raining on the Moon, but it does seem to be getting wetter and wetter.
For decades, the prevailing view of the Moon was that it was dry. Then, two years ago, a NASA probe crashed into a deep crater near the Moonâ€™s south pole and confirmed large amounts of water ice within the shadows. Meanwhile, measurements by an orbiting Indian spacecraft suggested that a veneer of water, generated by the bombardment of solar wind particles, covered much of the Moonâ€™s surface.
Now, scientists analyzing tiny fragments of hardened lava from long-ago lunar eruptions report that the fragments contain about as much water as similar magmas on Earth, meaning there is plenty of water inside the Moon too.