Using the planet-hunting NASA's Kepler Space Telescope, researchers identified the planet as Kepler-186f that is 1.11 times the radius of the earth.
"The discovery of Kepler-186f is a significant step toward finding worlds like our planet earth," said Paul Hertz, NASA's astrophysics division director at the agency's headquarters in Washington, DC.
Kepler-186f is part of a multi-planet system around the star Kepler-186, which has five planets, one of which is in the center of the habitable zone.
"We know of just one planet where life exists - earth. Finding a habitable zone planet comparable to earth in size is a major step forward," added lead author Elisa Quintana, a research scientist at the SETI Institute at NASA's Ames Research Center in Moffett Field, California.
The host star, Kepler 186, is an M1-type dwarf star, which means it would burn hydrogen forever, so there is ample opportunity to develop life around this particular star.
"The intensity and spectrum of radiation from Kepler-186f indicate that the planet could have an earth-like atmosphere and water at its surface which is likely to be in liquid form," revealed co-author Justin R. Crepp, a professor of physics from University of Notre Dame in Australia.
The next steps in the search for distant life include looking for true earth-twins and measuring their chemical compositions, said the study published in the journal Science.