Never mind that you would have to travel at the speed of light for 500 years to reach it – an earth like planet has been discovered in the “habitable zone” of a distant star. NASA’s Kepler telescope has identified “Kepler-186f” as the first concrete proof “habitable” earth size planets orbit other stars.
The habitable zone describes a cosmic sweet spot – not too hot, not too cold, but just right – a planet orbiting at the proper distance from its star to support liquid surface water. Kepler 186f, slightly larger than Earth, orbits its star once every 130 days. In the “zone”, but with a more distant orbit than one our planet enjoys, 186f is handicapped by a sun’s brightness at noon shining as ours would an hour before sunset.
As for probability it supports life, at least as we know it? Science reserves opinion until we’re able to determine mass and atmosphere. My guess is that within the next few decades, proof positive of extraterrestrial life will become a reality.