One in five stars similar to the Sun is circled by an Earth-like planet that might be habitable, scientists believe.
Researchers came to the conclusion after reviewing four years' worth of data from the American space agency Nasa's Kepler space telescope.
It means our galaxy, the Milky Way, could potentially be teeming with Earth-like life.
Erik Perigura, from the University of California at Berkeley, said: "What this means is, when you look up at the thousands of stars in the night sky, the nearest sun-like star with an Earth-size planet in its habitable zone is probably only 12 light years away and can be seen with the naked eye.
"That is amazing."