Posted on 03/07/2008 2:28:00 PM PST by jmcenanly
Earth may have a twin orbiting one of our nearest stellar neighbors, a new study suggests.
University of California, Santa Cruz graduate student Javiera Guedes used computer simulations of planet formation to show that terrestrial planets are likely to have formed around one of the stars in the Alpha Centauri star system, our closest stellar neighbors.
Guedes' model showed planets forming around the star Alpha Centauri B (its sister star, Proxima Centauri, is actually our nearest neighbor) in what is called the "habitable zone," or the region around a star where liquid water can exist on a planet's surface.
The model also showed that if such planets do in fact exist, we should be able to see them with a dedicated telescope.
"If they exist, we can observe them," Guedes said.
Guedes' study has been accepted for publication in the Astrophysical Journal.
A likely candidate
Astronomers have for some time pinned the Alpha Centauri system as one that was likely to form planets, said study co-author Gregory Laughlin, a UCSC professor.
"I think that there's been a good line of evidence over the past decade or so," Laughlin told SPACE.com.
Several factors mark the system, particularly Alpha Centauri B as friendly to planet formation, Laughlin said. The metallicity of Alpha Centauri B (or how much of its matter is made up of elements heavier than hydrogen and helium) is higher than our Sun's, so there would be plenty of heavier-mass material for planets to form from, he said.
Laughlin also noted that a number of factors make Alpha Centauri B a good candidate for astronomers to actually detect an Earth-sized terrestrial planet.
(Excerpt) Read more at space.com ...
Um, and what do you say to the residents there, if they are there? ... ‘Care to share?’ ‘Mind if we start scrutinizing you ... for our reasons?’
Remember, it is only possible. Nobody has seen anything in that expected location as yet.
The development of life on earth was a one for one, not a looooong shot ... it didn’t happen by accident. Too many variables ALL fell into perfect place and at the exact right timing.
Or not
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