A Wet Luna

Scientists studying recently discovered evidence of water on the Moon are breaking that resource down into three categories. One is the large chunks of water ice found, so far, in 40 craters in the north polar regions. Another is the water ice found in permanently shadowed craters in the south polar regions. A third category is the trace surface water that seems to roam over large areas, and a subsurface layer of water ice that also seems to exist over large areas.

Whether the three categories in fact interact to form a coherent, functioning system of some sort is not known. Scientists, however, believe the water came from various sources. Some of it seems to be indigenous to the Moon, while some seems to have come from elsewhere in space.

While searching for water, scientists have also found other chemicals not heretofore thought to be on the Moon, including trace organics. This is not Neil Armstrong's Luna.