A planet, as depicted in this rendering, orbits the habitable zone of a star 20 light years from Earth, meaning it could have water on its surface.
It might be a place that only a lichen or pond scum could love, but astronomers said Wednesday that they had found a very distant planet capable of harboring water on its surface, thus potentially making it a home for plant or animal life.
Nobody from Earth will be visiting anytime soon: The planet, which goes by the bumpy name of Gliese 581g, is orbiting a star about 20 light-years away in the constellation Libra.
But if the finding is confirmed by other astronomers, the planet, which has three to four times the mass of Earth, would be the most Earthlike planet yet discovered, and the first to meet the criteria for being potentially habitable.
“It’s been a long haul,” said Steven S. Vogt of the University of California, Santa Cruz, who, along with R. Paul Butler of the Carnegie Institution of Washington, led the team that made the discovery. “This is the first exoplanet that has the right conditions for water to exist on its surface.”