NASA's Kepler Mission Discovers Earth's Bigger, Older Cousin

The Kepler probe's focus is on finding another habitable planet.

ByABC News
July 23, 2015, 1:07 PM

— -- NASA says we're on our way to discovering Earth 2.0.

The Kepler Space Telescope has located a planet and star closely resembling Earth and the Sun, NASA officials said. The newly discovered planet, which NASA has named Kepler-452b, is believed to be 6 billion years old -- making it about 1.5 billion years older than the Earth and our sun. NASA said the star, Kepler-452, also has the same temperature as our Sun and has a diameter 10 percent larger.

The system is located 1,400 light-years from Earth in the constellation Cygnus. What makes the discovery especially intriguing is that the planet is orbiting the habitable zone of the solar system, the "Goldilocks" region where it's not too hot or too cold, so that the surface of the planet could sustain liquid water.

"It’s awe-inspiring to consider that this planet has spent 6 billion years in the habitable zone of its star; longer than Earth," said Jon Jenkins, Kepler's data analysis lead. "That’s substantial opportunity for life to arise, should all the necessary ingredients and conditions for life exist on this planet."

While the planet's mass and composition are still unknown, scientists have determined the planet is 60 percent larger in diameter than Earth and has a slightly longer orbit around its star -- clocking in at 385 days.

Kepler began its quest to find Earth-like planets in 2009. Today's announcements comes as NASA completed an initial analysis of data from the telescope, which has discovered more than 4,600 planets and planet candidates.