On Thursday (April 17), NASA announced the historic discovery of Kepler-186f, an alien planet 490 light-years from our own world that is nearly the size of Earth and located inside the habitable zone of its parent star.
The planet Kepler-186f was discovered by scientists using NASA's planet-hunting Kepler space telescope. The planet has a radius that is 1.1 times the radius of Earth, making it only slightly larger than our planet.
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