A near-Earth-size planet in the “habitable zone” around a sun-like star has been discovered, called Kepler-452b. Habitable zone being, “the area around a star where liquid water could pool on the surface of an orbiting planet — of a G2-type star, like our sun,” said NASA. The find of Kepler-452b brings the total number of confirmed planets to 1,030.
“On the 20th anniversary year of the discovery that proved other suns host planets, the Kepler exoplanet explorer has discovered a planet and star which most closely resemble the Earth and our Sun,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at the agency’s headquarters in Washington. “This exciting result brings us one step closer to finding an Earth 2.0.”
Earth is much smaller in diameter, with Kepler-452b being 60 percent larger. Kepler-452b has a 385-day orbit, which is only 5 percent longer than Earth’s. NASA says Kepler-452 is 6 billion years old, which is 1.5 billion years older than our sun. It also has the same temperature, and is 20 percent brighter and has a diameter 10 percent larger.
“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 in Moffett Field, California, who led the team that discovered Kepler-452b. “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.”
Kepler-452b find increases the number of new exoplanet candidates by 521 from analysis of observations conducted from May 2009 to May 2013, raising the number of planet candidates detected by the Kepler mission to 4,696.
“We’ve been able to fully automate our process of identifying planet candidates, which means we can finally assess every transit signal in the entire Kepler dataset quickly and uniformly,” said Jeff Coughlin, Kepler scientist at the SETI Institute in Mountain View, California, who led the analysis of a new candidate catalog. “This gives astronomers a statistically sound population of planet candidates to accurately determine the number of small, possibly rocky planets like Earth in our Milky Way galaxy.”