NASAs Kepler planet-finding space telescope has found three "super Earths" orbiting in the habitable zone of two distant stars, including one only 40% larger than Earth. Kepler-62f is believed to have a rocky composition. It and its larger habitable-zone companion, Kepler-62e, orbit a star dimmer and older than the Sun called a K2 dwarf that is 1,200 light years from Earth in the constellation Lyra. A third exoplanet-Kepler-69c-has been confirmed in the habitable zone of a Sun-like star in the constellation Cygnus 2,700 light years from Earth. It measures 70% larger than Earth, and has a 242-day orbit that approximates that of Venus in our Solar System. "We wouldn't describe these as Earth-like planets," says Thomas Barclay, the Kepler scientist at the Bay Area Environmental Research Institute in Sonoma, Calif., who was lead author on a Kepler-69 system paper published last week. "We simply don't know if other Earth-like planets are out there yet."
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