NASA announced the discovery of 12 new habitable zone planets, including one identified as Earth’s “bigger, older cousin” on July 23, 2015.
NASA’s Kepler mission is responsible for the discovery of over 1,000 planets in total, but one, Kelper-452b, is remarkable because it is the smallest planet discovered orbiting in a star’s habitable zone, a set of orbits where environmental conditions could facilitate the presence of liquid water.
John Grunsfeld, associate administrator of NASA’s Science Mission Directorate said the result brings us one step closer to finding Earth 2.0:
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…
According to NASA, Kepler 452-b is 60 percent larger than Earth and has an orbital period of 385 days, which is 5 percent longer than Earth’s year. Kepler 452-b is also 1.5 billion years older, checking in a 6 billion years old.
Ground based observations from the University of Texas-Austin’s McDonald Observatory, the Fred Lawrence Whipple Observatory on Mount Hopkins in Arizona, and the W. M. Keck Observatory on Mauna Kea, Hawaii confirmed the size and orbit of the planet, as well as the size and brightness of the star the planet is orbiting.
Kepler-452 is 1,400 light-years away from Earth in the constellation Cygnus.
Kepler 452-b is the best candidate discovered by the Kepler mission thus far to have life on it. Jon Jenkins, Kepler data analysis lead at NASA Ames Research Center in Moffett Field, California, said the following:
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.
12 of the new planets are between one and two times the diameter of Earth and have orbits in their star’s habitable zones. Of the 12, nine orbit stars with size and temperature comparable with our sun.