The habitable zone, also known as the Goldilocks zone, is the region around a star within which planetary-mass objects with sufficient atmospheric pressure can support liquid water at their surfaces. While it has been estimated that there are at least 40 billion Earth-sized planets orbiting in our Milky Way Galaxy, this particular discovery is labeled the first Earth-sized planet to be found in the habitable zone of another star.
NASA’s Kepler Space Telescope recently discovered an Earth-like planet orbiting a nearby star within the habitable zone of our galaxy. Kepler-186f is approximately 500 light-years from Earth in the Cygnus constellation.
In addition to Kepler-186f, there are 4 other planets that orbit a nearby star within the Kepler-186f system. What this means is that if the nearby star to this planet is similar to our Sun, then the probability of life on this planet exponentially rises.
“We know of just one planet where life exists – Earth. When we search for life outside our solar system we focus on finding planets with characteristics 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 today in the journal Science.
The nearby star to Kepler-186f has half the mass and size as our solar system’s Sun and only receives one-third of the energy that we receive from our Sun. Kepler-186f orbits its star once every 130 days.