Schematic of habitable zone of different planets

Credit: NASA Kepler Mission

Habitable alien planets similar to Earth may not be that rare in the universe, a new study suggests.

About one in five sunlike stars observed by NASA’s planet-hunting Kepler spacecraft has an Earth-size planet in the so-called habitable zone, where liquid water — and, potentially life — could exist, according to the new study. If these results apply elsewhere in the galaxy, the nearest such planet could be just 12 light-years away.

“Human beings have been looking at the stars for thousands of years,” said study researcher Erik Petigura, a graduate student at the University of California, Berkeley (UC Berkeley). “How many of those stars have planets that are in some way like Earth? We’re very excited today to start to answer that question,” Petigura told SPACE.com.

via Earth-Size Alien Planets Common Across the Universe, Study Suggests | Space.com.