Kepler Discovers Earth's Older Sister

NASA’s Kepler space telescope has found the closest match yet to a world that is similarly sized to Earth and circling a sun-like star at the right distance for liquid surface water, a condition believed to be necessary for life, scientists said Thursday.

The newly found world, called Kepler-452b, is located about 1,400 light-years away in the constellation Cygnus.

“In my mind, this is the closet thing we have to another planet like the Earth,” Jon Jenkins, head of Kepler data analysis at NASA's Ames Research Center in Moffett Field, Calif., told reporters on a conference call Thursday.

Kepler-452b is about 60 percent wider than Earth and estimated to have five times the mass, making it most likely a rocky world. It circles a G-type star very much like the sun, but estimated to be closer to 6 billion years old, compared to the 4.6-billion-year age of the solar system.

“That’s a considerable opportunity for life to arise, should all the necessary ingredients and conditions for life exist on this planet,” Jenkins said.

“It’s simply awe-inspiring to consider that this planet has spent 6 billion years in the habitable zone of its star,” Jenkins said. “That’s considerable time and opportunity for life to arise somewhere on its surface, or in its oceans, should all the necessary ingredients and conditions for life exist on this planet.”

Kepler-452b orbits its parent star every 385 days, so it is located just about 5 percent farther away from the star than Earth circles the sun. The star’s age means it’s about 10 percent bigger and 20 percent brighter than the sun, Jenkins said.

If Kepler-452b is rocky, scientists expect it would be about five times more massive than Earth and twice Earth’s surface gravity. It would have a thicker, cloudier atmosphere and most likely active volcanoes, Jenkins added.

Read more at Discovery News