Nice to know there is a theory that might be able to judge where ET could spring up from.

Not too far away in Space terms either....

Quote


The idea, based on the leading planet-formation theory, is that small objects collect more material and, if they don't collide with another big object, become planets.


Star of the show


Only 55 Cancri consistently yielded a world similar in size and orbital distance to Earth. Our planet sits in what's called a habitable zone, just the right distance from the Sun to allow liquid water.


"Our simulations typically produced one terrestrial planet in the habitable zone of 55 Cancri, with a typical mass of about half an Earth mass," said Sean Raymond, a postdoctoral researcher at the University of Colorado who worked on the project while a doctoral student at the University of Washington. "In many of the simulations, these planets accreted a decent amount of water-rich material from farther out in the disk."


The research, funded by NASA and the National Science Foundation, is described in a recent issue of the Astrophysical Journal.


A computer simulation is of course far from reality. But research like this can guide astronomers to solar systems worthy of further investigation as search technology improves.


"Our assumptions are quite optimistic, but not crazy by any means, and we start our simulations with a decent amount of material for terrestrial planets to form," Raymond told SPACE.com. "If we are wrong about this, then only smaller, perhaps Mars-sized planets could form in the habitable zone."

http://www.space.com/scienceastronomy/0608...ce_tuesday.html