Saturday science subject: Earth's fat cousin
Astronomers have uncovered the first extrasolar planet they believe could have liquid water on its surface and support life forms, Space.com reports. The planet is a bit bigger than the earth—50% larger and five times more massive, to be precise—but it's the smallest extrasolar planet yet found and a far cry from the brown dwarfs and Jupiter-like gas giants that have been detected in remote star systems so far.
Astronomers say this planet, which they have dubbed Gliese 581 C, sits within the "Goldilocks zone" of its host star. That means it's not far enough potential water on its surface would freeze but not so close that water would simply evaporate (like the evaporating exoplanet from our previous Saturday science post). According to Stephane Udry of the Geneva Observatory in Switzerland, the mean temperature on Gliese 581 C is between 0 and 40 degrees Celsius, or 32-104 degrees Fahrenheit. The planet could harbor life, although it is a little far away for us to send a recon mission there just yet. Gliese 581 C is 20.5 light years from Earth in the constellation Libra.