The Martian permafrost may be hiding veins of habitable liquid water

Mars may have a network of liquid water flowing through the frozen ground. All buried permafrost, on Earth and beyond, is expected to host narrow veins of liquid, and new calculations show on Mars, they could be big enough to support living organisms. "For Mars we always live on the edge of maybe habitable, maybe not, so I set out to do this research thinking maybe I can close this loop and say that it's very unlikely to have enough water and have it be arranged so that it's habitable for microbes," says Hanna Sizemore at the Planetary Science Institute in Arizona. She and her colleagues used measurements of the soil composition on Mars to calculate how much of the icy soil could actually be liquid water and the size of the channels that water would run through. It is tricky to keep water liquid on Mars, because temperatures can get as low as -150 C (-240 F) on the planet.