Kepler 186F Is First Earth Like Planet Discovered In A Nearby Star Habitable Zone

For the past three decades, the SETI Institute has been participating in a number of scientific explorations to answer the question "Are we alone?" Today, my co-authors and I are announcing the achievement of another milestone in the exploration. We have confirmed the first Earth-sized planet orbiting in the habitable zone of a star other than the Sun.

This planet is named Kepler-186f and it is one of five planets that have thus far been detected by NASA's Kepler space telescope in orbit about the star Kepler-186. This star is smaller and cooler than the Sun, of a type called an M-dwarf or red dwarf, and all its known planets are small as well, with sizes less than 1.5 times the size of Earth. The planet Kepler-186f is the smallest, being within 10% of the size of Earth and orbits furthest from the host star, within the habitable zone. This is the region around a star within which a planet can sustain liquid water on its surface given the right atmospheric conditions. The Kepler-186 planetary system lies in the direction of the constellation Cygnus, about 500 light-years away.