Two 'new Earths' found by Kepler space probe Dec 21, 2011 16:21:09 GMT 1
Post by uforn on Dec 21, 2011 16:21:09 GMT 1
Two 'new Earths' found by Kepler space probe as 'alien life' edges closer
Nasa appears to be closing in on finding a planet that closely resembles Earth and can support alien life, after the Kepler telescope tracked down two celestial bodies of almost identical sizes to us.
A Nasa artist's rendering of new planet Kepler-20e (Picture: Reuters)
Following on from the discovery of Kepler-22b earlier this month, which had the same ambient atmospheric temperature as Earth and most likely has water on its surface, the finding is being hailed as a 'milestone'.
However, while both new planets - called Kepler-20e and Kepler-20f - are the right size, their orbits around their star are too short and therefore the surface temperatures are likely to be too short.
One year on Kepler-20e is just six days long while Kepler-20f's orbit is 19 days.
Astronomer David Charbonneau of Harvard University, who is involved in the space research project, said: 'Kepler-22b has the right temperature, but it is too big. [The planets] we're announcing today are just the right size, but too hot.
'But you can bet that the hunt is on to find a planet that combines the best of both worlds, a true Earth twin.'
Although researchers have ruled out alien life on both new discoveries, they have suggested the two planets were not always insufficient to support ecosystems similar to Earth's.
A planetary 'line-up' depicting the Earth-sized extrasolar planets Kepler-20e and Kepler-20f, alongside Earth and Venus (Picture: PA)
'If Kepler-20f was formed with water, which I think is likely, then it could have held on to its water for several billions of years,' said astronomer Linda Elkins-Tanton with the Carnegie Institute in Washington DC.
'That means this planet could have been habitable in the past for a long period.'
The Kepler solar system is located approximately 1,000 light-years from Earth, and part of the constellation, Lyra.