This artist conception illustrates Kepler-22b, a planet known to comfortably circle in the habitable zone of a sun-like star. It is the first planet that NASA Kepler mission has confirmed to orbit in a star habitable zone.
Closer to Finding an Earth Artist Concept
This diagram compares our own solar system to Kepler-22, a star system containing the first habitable zone planet -- the sweet spot around a star where temperatures are right for water to exist in its liquid form, discovered by NASA Kepler mission.
Kepler-22b -- Comfortably Circling within the Habitable Zone
A newly discovered exoplanet, Kepler-452b, comes the closest of any found so far to matching our Earth-sun system. This artist's conception of a planetary lineup shows habitable-zone planets with similarities to Earth: from left, Kepler-22b, Kepler-69c, the just announced Kepler-452b, Kepler-62f and Kepler-186f. Last in line is Earth itself.  http://photojournal.jpl.nasa.gov/catalog/PIA19830
Pantheon of Planets Similar to Earth Artist Concept
Kepler Program VIP's from left Natalie Batalha, Bill Borucki and Jon Jenkins in front of a NASA Ames Hyperwall display of newly discovered planet K-22B art at the NAS (NASA Advanced Supercomputing) Facility, Moffett Field, CA (for aviation week)
ARC-2012-ACD12-0022-007