Last updated on April 23, 2014 at 15:23 EDT

Kepler Mission Finds Earth-size Planet Candidates

February 4, 2011

NASA’s Kepler mission has discovered its first Earth-size planet candidates and its first candidates in the habitable zone, a region where liquid water could exist on a planet’s surface. Five of the potential planets are near Earth-size and orbit in the habitable zone of smaller, cooler stars than our sun. credit: NASA