NASA's Kepler Mission Announces Latest Planetary Discovery

The Kepler mission's science team announced its latest finding at a press conference on Monday, Dec. 5, 2011. The team announced the confirmation of Kepler-22b, its first planet found in the "habitable zone," the region where liquid water could exist on a planet's surface. The planet is about 2.4 times the radius of Earth, orbits around a star similar to our sun and is located 600 light-years away. Scientists don't yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition,