planet circling red dwarf

D. Aguilar/Harvard-Smithsonian Center for Astrophysics


Humanity's next home could be circling a strange type of star, known as a red dwarf, a new study suggests.

A red dwarf is a type of star that is smaller than our sun. They are also cooler and fainter. Because of that, a planet orbiting these stars would need to be closer to it than we are to the sun.

The new study found that planets that circle these weakling stars at a certain distance could be habitable — meaning the planet could have liquid water and potentially support life. It will be published in an upcoming issue of The Astrophysical Journal.

The researchers, are the Harvard-Smithsonian Center for Astrophysics, used data from NASA's Kepler telescope (which has been searching for planets circling other stars since 2009) to determine that about six percent of red dwarves have an Earth-sized planet in their habitable zone.

They actually found three planets from the survey that could be good candidates, but they are between 300 and 600 light-years away. They are: 1422.02, which is 90 percent the size of Earth in a 20-day orbit; KOI-2626.01, 1.4 times the size of Earth in a 38-day orbit; and KOI-854.01, 1.7 times the size of Earth in a 56-day orbit.

Red dwarves are by far the most common stars out there (they make up 75 percent of stars), but they aren't as easy to see as brighter stars. Actually, none of the stars we see in the sky are red dwarves, but they are out there en masse.

Because many of our sun's neighbors are red dwarves, the researchers that statistically, it's possible that there could be an Earth-like planet just 13 light-years away.

The researchers don't know if life could exist on such a planet, though, because being closer to your sun means the planets are more at risk from solar flares, gravity, and radiation from the sun. Interestingly, since it would be so close to the star, the planet would be tidally locked — meaning it would have a dark side and a light side.

It could also be much older than Earth, since red dwarves live much longer star-lives than larger stars like our sun.