Astronomers discover potentially life-sustaining planetby Steven Mostyn - Sep 30 2010, 20:16
An artist's impression of Gliese 581G orbiting its red dwarf star. Image: Wikimedia Commons.
Not that we're likely to make the journey to a new life-sustaining world any time soon, but it's at least nice to know there's one out there. Specifically, stargazing scientists at the Lick-Carnegie Exoplanet Survey have discovered a nearby planet they believe has a climate ideal for forming life.
According to the research report submitted to The Astrophysical Journal, planet 'Gliese 581G' has an estimated equilibrium temperature of 228 Kelvin, which places it slap-bang in the middle of the habitable zone of its nearby star and offers "a very compelling case for a potentially habitable planet…"
Gliese 581G is situated some 20 light years from our own solar system and is described as a minimum mass 3.1 M_Earth planet orbiting .146 AU with a period of 36.6 days.
"That a system harbouring a potentially habitable planet has been found this nearby, and this soon in the relatively early history of RV [Radial Velocities] indicate that eta-Earth, the fraction of stars with potentially habitable planets, is likely to be substantial," the report adds.
Radial Velocities are the measurement of the speed at which an object is moving towards or away from an observer.
The scientists also believe the planet is likely to have surface temperatures averaging between -37° C and -15° C, largely because its M_class dwarf star is only producing a fraction of the heat emitted by the sun in our own solar system.
"If this local stellar neighbourhood is a representative sample of the galaxy as a whole, our Milky Way could be teeming with potentially habitable planets," the Lick-Carnegie scientists posited.
During a recent interview with the National Science Foundation, during which Lick-Carnegie principal investigator Steven Vogt was asked his views regarding the possibility of life existing on Gliese 581G, he said:
"Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say that, my own personal feeling is that the chances of life on this planet are 100%. I have almost no doubt about it."