October 1, 2007

Gliese 581c: An Extrasolar Earth?

Gliese 581 c, the incredibly creative name of a planet found orbiting red dwarf Gliese 581, is not like any exoplanets we know. Most exoplanets are huge, massive, gas giants. They often are hot as lava, called hot 'jupiters', or five times as cold as our arctic. But not Gliese 581c. If we had to pick which exoplanet had life on it, all bets would be on Gliese 581 c, and here's why.

Gliese 581 c is located in "the habitable zone". The habitable zone is the exact distance from the Sun (or another star) that a planet can be at that liquid water will not permanently freeze or completely evaporate. Gliese 581 c is located within the habitable zone of its star, Gliese 581, and if liquid water were present on the surface, it would act and behave much the same way it would on Earth.

Current models predict Gliese 581 c is either a very rocky planet, or a complete oceanic planet, with no visible land. Either way there is no way to know for sure (yet) what the surface of this planet holds.

All bets are on Gliese 581 c. Gliese 581c X-Prize anyone?