Planet hunters say they've identified the first planet orbiting a distant star with conditions right to sustain liquid water and, perhaps, life. The planet, Gliese 581g, is about 3 to 4 times the mass of Earth and circles Gliese 581, a red dwarf star located 20 light years away from Earth in the constellation Libra. The astronomers say it likely has a rocky surface, gravity enough to sustain an atmosphere, and lies in a temperature range in which liquid water could exist.
The planet is no paradise, however. The researchers believe the planet is tidally locked to the star, with one side always facing the star and the other in constant night. The side of the planet facing its star would likely be blazing hot, while the side pointed away from the star would be freezing cold. Still, with stable temperatures, the possibility exists that extremophiles of some sort could survive on the planet's surface.
Intriguingly, the planet was found relatively rapidly, raising the possibility that such planets might be relatively common in the universe. We'll talk about the discovery and what it means to the hunt for distant worlds.
Produced by Flora Lichtman, Correspondent and Managing Editor, Video