With newly discovered signs of liquid water, a moon of Saturn joins the small, highly select group of places in the solar system that could plausibly support life. The moon, Enceladus, is only 300 miles wide, and usually something that small is nothing more than a frozen chunk of ice and rock. Instead, NASA's Cassini spacecraft has spotted eruptions of icy crystals, which hint at pockets of liquid water near the surface. NY Times