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.

While it has been projected that there are at least 40 billion Earth-sized planets circling in our Milky Way Galaxy, this specific finding is labelled the first Earth-sized planet to be discovered in the habitable zone of another star.

What does this mean?

In addition to Kepler-186f, there are 4 other planets that circle a nearby star within the Kepler-186f system. What this means is that if the neighbouring star to this planet is just like our Sun, then the likelihood of life on this planet exponentially increases.

“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.”

The neighboring star to Kepler-186f has half the mass and size as our solar system’s Sun and only gets one-third of the energy that we get from our Sun. Kepler-186f circles its star once every 130 days.