Just a day after NASA announced there is water on the Moon, another study indicates virtually pure water ice exists on the surface of Mars. The ice, some scientists speculate, may be a remnant of a climate on Mars, perhaps as few as 10,000 years ago, that was warmer and wetter than today. The study also suggests underground water exists over about half the planet, and estimates that the total amount of water on Mars may equal the amount locked in the Greenland ice sheet. Used correctly, then, there would seem to be enough water on Mars to support a small society.
Just as scientists may have misinterpreted suggestions of water in Apollo rock samples, so they may have barely missed confirming water on Mars thirty years ago. Had NASA's lander Viking 2 dug just four inches deeper into the soil, it rests at a lattitude that may have allowed it to discover water.
Clearly, the twin announcements this week buoy the prospects of human settlements throughout the Solar System. The next step is confirming these early indications. Assuming that's done, the hard but joyous work of planting outposts on other worlds can begin in earnest.