Scientists say the temperature on the surface of the planet is about a comfy 72 degrees. Its star could almost be a twin of our sun. It likely has water and land.
It was found in the middle of the habitable zone, making it the best potential target for life yet.
The discovery announced Monday was made by NASA's Kepler planet-hunting telescope. This is the first time Kepler confirmed a planet outside our solar system in the not-too-hot, not-too-cold habitable zone.
Twice before astronomers have announced a planet found in that zone, but neither was as promising. One was later disputed; the other is on the hot edge of the zone.