`Potentially Habitable' Planet Discovered Orbiting Nearby Star
Gliese 581 Illustration
Lynette Cook/NASA via Bloomberg
An artist's conception shows the inner four planets of the Gliese 581 system and their host star, a red dwarf star 20 light years away from Earth. The planet in the foreground is the newly discovered GJ 581g, which has a 37-day orbit and is only three to four times the mass of Earth.
An artist's conception shows the inner four planets of the Gliese 581 system and their host star, a red dwarf star 20 light years away from Earth. The planet in the foreground is the newly discovered GJ 581g, which has a 37-day orbit and is only three to four times the mass of Earth. Source: Lynette Cook/NASA via Bloomberg
An Earth-sized planet has been discovered orbiting a nearby star at a distance that scientists say might allow it to have water and support life.
The planet was one of two discovered by a team led by astronomers at the University of California, Santa Cruz, and the Carnegie Institution of Washington. They circle Gliese 581, a dwarf star 20 light years from Earth that forms part of the constellation Libra.
The planet’s distance from Gliese 581 places it in the middle of the star’s “habitable zone,” Steven Vogt, a professor of astronomy and astrophysics at UC Santa Cruz, said in a statement. The planet probably has a rocky surface and enough gravity to hold an atmosphere, he said.
“Our findings offer a very compelling case for a potentially habitable planet,” Vogt said. “We had planets on both sides of the habitable zone -- one too hot and one too cold -- and now we have one in the middle that’s just right.”
One side of the possibly livable planet, dubbed Gliese 581g, always faces the star and is in perpetual daylight while the other side faces away and is always dark, Vogt said. Temperatures probably range from blazing hot on the daylight side to subfreezing cold on the dark side.
The findings of Vogt and his colleagues were published today in the Astrophysical Journal. The team was funded by the National Science Foundation, which announced the finding.
The two newly discovered planets brings to six the number of planets known to orbit Gliese 581, according to the foundation. The findings are based on 11 years of observations from the W.M. Keck Observatory in Hawaii.
To contact the reporter on this story: Rob Waters in San Francisco at rwaters5@bloomberg.net.
To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net.
Rate These Stories
Rate this Page