NASA Discovers First Earth-like Planet Orbiting a Sun-like Star with Kepler

First Posted: Jul 23, 2015 05:58 PM EDT

NASA's Kepler Mission has officially discovered the first near-Earth-size planet in the "habitable" zone around its sun-like star. The findings could mark a milestone in the space agency's journey to find a second Earth.

The new planet is called Kepler-452b. It's actually the smallest planet to date discovered orbiting in the habitable zone, which is the area around a star where liquid water could pool on the surface of an orbiting planet. It's currently orbiting a G2-type star, which is a star that's similar to our sun.

"On the 20^th anniversary year of the discovery that proved other suns host planets, the Kepler exoplanet explorer has discovered a planet with a star which most closely resembles the Earth and our sun," said John Grunsfield, associate administrator of NASA's Science Mission Directorate, in a news release. "This exciting result brings us one step closer to finding an Earth 2.0."

With that said, there are differences between the planet and Earth. For one, Kepler-452b is about 60 percent larger in diameter than Earth, and is considered to be a super Earth. Its mass and its composition are also not yet determined, though researchers believe that there is a very good chance of it being rocky.

"We can think of Kepler-452b as an older, bigger cousin to Earth, providing an opportunity to understand and reflect upon Earth's evolving environment," said Jon Jenkins, Kepler data analysis lead at NASA's Ames Research Center. "It's awe-inspiring to consider that this planet has spent 6 billion years in the habitable zone of its star; longer than Earth. That's substantial opportunity for life to arise, should all the necessary ingredients and conditions for life exist on this planet."

The planet is located 1,400 light-years away in the constellation Cygnus. However, the researchers will have to continue to study this planet in order to learn a bit more about it and whether or not it could support life.

The findings are published in The Astronomical Journal.