By Nadia Drake
BEIJING — A potentially habitable planet has been discovered orbiting the star Gliese 163, 50 light-years away. The planet is bigger than Earth — roughly seven times as massive — and resides near the inner edge of the star’s habitable zone, Thierry Forveille of France’s Observatoire de Grenoble reported on August 30 at the International Astronomical Union’s general assembly meeting. Depending on its composition and how insulating its atmosphere is, the planet could be capable of supporting life.
“I’d say that’s a habitable planet,” said Raymond Pierrehumbert of the University of Chicago. It’s unlikely the planet would experience any sort of runaway greenhouse effect that would heat it beyond the point of livability, he says.
Forveille and his colleagues found the planet by searching for wobbles in the planet’s host star with a telescope in Chile. Astronomers calculate that Gl 163c, as the planet is called, receives 30 to 40 percent more energy than Earth receives from the sun. Because the planet’s radius is unknown, it’s not yet clear what the planet is made of, but scientists speculate that it’s a mix of rock and water.