Relative sizes of Kepler habitable zone planets discovered as of 2013 April 18. Except for Earth, these are artists' renditions.

Relative sizes of Kepler habitable zone planets discovered as of 2013 April 18. Except for Earth, these are artists' renditions.

NASA's Ames Research Center in Moffett Field, Calif., manages Kepler's ground system development, mission operations and science data analysis. JPL managed the Kepler mission's development.

For more information about the Kepler mission, visit: http://www.nasa.gov/kepler.

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