'Meet Kepler-186f, the most 'Earth-like' planet ever found
Sifting through observations from tens of thousands of distant stars, astronomers say they have discovered the first definitive Earth-sized planet that orbits in a habitable zone where water could exist in liquid form — a necessary condition for life as we know it.
Experts don't know if the planet, described in Friday's edition of the journal Science, actually has water or a protective atmosphere. They don't even know its mass. But they said the landmark discovery raises the distinct possibility that a bumper crop of Earth-like planets is waiting to be found much closer to home, including around temperamental stars that until recently were considered inhospitable to life.'