Finding Twin Earths Is Harder Than We Thought 161
Matt_dk writes "Does a twin Earth exist somewhere in our galaxy? Astronomers are getting closer and closer to finding an Earth-sized planet in an Earth-like orbit. NASA's Kepler spacecraft just launched to find such worlds. Once the search succeeds, the next questions driving research will be: Is that planet habitable? Does it have an Earth-like atmosphere? Answering those questions will not be easy. 'We'll have to be really lucky to decipher an Earth-like planet's atmosphere during a transit event so that we can tell it is Earth-like,' said Kaltenegger. 'We will need to add up many transits to do so — hundreds of them, even for stars as close as 20 light-years away.'" The abstract of their paper offers a link to the complete paper as a 17-page PDF; here is a short description from 2007 of the same researchers' work, outlining the type of spectral signature that an Earth-like atmosphere would be expected to show.
Re:Wrong Approach? (Score:5, Informative)
I don't think the idea is to find a new place for us to live. Obviously, our ability to take advantage of such a planet is incredibly limited.
Rather, its to understand what the possibilities for life outside our planet are. Putting it in simplest terms, its working to get experimental data for some of the coefficients in the Drake equation.
Just call it an M-class planet already (Score:2, Informative)
Re:Time difference (Score:5, Informative)
In the range of 20lyrs there are about 100 stars, in the range of 250lyrs about 260000.
See: http://www.atlasoftheuniverse.com/ [atlasoftheuniverse.com]
angel'o'sphere