National Aeronautics and Space Administration (NASA) announced Tuesday that a planet of rock, orbiting extremely close to its host star, has been identified as the smallest ever discovered outside the solar system. It is also the first rocky, or Earth-like planet discovered by Kepler.
Dubbed Kepler-10b, the exoplanet is about 560 light years from Earth. And with 1.4 times the size of Earth, Kepler-10b is more than 20 times closer to its star than Mercury is to the sun, and whips around the star once every 0.84 days.
This makes it impossible for life to exist on the exoplanet, according to NASA. It's so hot that boiled iron and silicates are flowing into the stellar wind, much like a comet's tail.
Still, the discovery has scientists optimistic about what else Kepler might be able to reveal. "Although this planet is not in the habitable zone, the exciting find showcases the kinds of discoveries made possible by the mission," said Kepler program scientist Douglas Hudgins.