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At Last, Earth-Sized Alien Worlds (Infographic)

Infographics
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The Kepler space telescope has spied evidence of two Earth-sized worlds in a star system 950 light-years away.
The Kepler space telescope has spied evidence of two Earth-sized worlds in a star system 950 light-years away. (Image credit: Karl Tate, SPACE.com Contributor)

On Dec. 20, 2011, astronomers announced the discovery an alien solar system 950 light-years from Earth that is chock full of planets, including the first two extrasolar worlds ever confirmed to be the size of our own Earth or smaller.

Finding Earth-size planets has been a major goal for NASA's Kepler space observatory, which spotted the small alien worlds and their larger cousins around a star known as Kepler 20. The two Earth-size planets (one is actually smaller than Earth) are known as Kepler-20e and Kepler-20f. See how the planets compare to Earth and the other planets in their alien star system in the infographic above. 

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Karl Tate
Karl Tate
Space.com contributor

Karl's association with Space.com goes back to 2000, when he was hired to produce interactive Flash graphics. From 2010 to 2016, Karl worked as an infographics specialist across all editorial properties of Purch (formerly known as TechMediaNetwork).  Before joining Space.com, Karl spent 11 years at the New York headquarters of The Associated Press, creating news graphics for use around the world in newspapers and on the web.  He has a degree in graphic design from Louisiana State University and now works as a freelance graphic designer in New York City.