> The nearest single star to the sun apparently hosts a big, icy planet.<p>> Astronomers have found strong evidence of a frigid alien world about 3.2 times more massive than Earth circling Barnard's Star, a dim red dwarf that lies just 6 light-years from the sun. Barnard's Star is our sun's nearest neighbor, apart from the three-star Alpha Centauri system, which is about 4.3 light-years away.