It's Official: Researchers Have Discovered A Second Earth
Researchers have confirmed the existence of a Second Earth. NASA’s Kepler Space Telescope discovered an Earth-like planet circling a nearby star within the Goldilocks zone of our galaxy. Kepler-186f is around 500 light-years from Earth in the Cygnus constellation. The habitable zone, also identified as the Goldilocks zone, is the area around a star within which planetary-mass objects with enough atmospheric pressure can sustain liquid water at their surfaces.
"We know of only one planet where life survives – Earth. When we hunt for life outside our solar system, we emphasis on discovering planets with features that mimic that of Earth," said Elisa Quintana, research scientist at the SETI Institute at NASA's Ames Research Center in Moffett Field, Calif., and lead author of the paper published in the journal Science. "Discovering a habitable zone planet similar to Earth in size is a major breakthrough."