When NASA astronauts first landed on the moon in 1969, they saw a desiccated world, bone-dry and devoid of any life-giving water. The Apollo astronauts, planning to stay only a few days, had brought plenty of water for their own needs. So this finding was disappointing for the hazy plans of future lunar outposts, but not immediately concerning.

Decades later, humans have learned that the only economical way to explore space longterm is to use the resources we find along the way. And lucki