Kepler confirms first planet in habitable zone of Sun-like star

Artist's conception of Kepler-22b. Credit: NASA/Ames/JPL-Caltech

Scientists from the Kepler mission announced this morning the first confirmed exoplanet orbiting in the habitable zone of a Sun-like star, the region where liquid water could exist on the surface of a rocky planet like Earth. Evidence for others has already been found by Kepler, but this is the first confirmation. The planet, Kepler-22b, is also only about 2.4 times the radius of Earth, the smallest planet found in a habitable zone so far, and orbits its star, Kepler-22, in 290 days. It is about 600 light-years away from Earth, and Kepler-22 is only slightly smaller and cooler than our own Sun. Since its mass is not yet known, it is not known yet if it is a rocky or gaseous planet, but its discovery is a major step toward finding Earth-like worlds around other stars. A very exciting discovery, but there’s more…

See Universe Today for the full article (December 5, 2011)