Scientists discover the first Earth-sized planet in its star’s habitable zone.
Since NASA’s Kepler space telescope launched in 2009, it has found hundreds of new worlds within the Milky Way. Now it has spotted the first planet outside our solar system that could support life. The planet, called Kepler-186f, is located about 500 light-years from Earth and orbits a star similar to our sun. Its orbit is within the star’s habitable zone, the region where temperatures should be neither too hot nor too cold, but just right for liquid water to exist—a precursor for life as we know it. Scientists are unsure if the planet is habitable or what it’s made of, but this discovery proves there are worlds like our own that reside in life’s celestial sweet spot. Watch the video for a tour of Kepler-186f.