A team at the University of Cardiff (go Cymry!) has decided the odds are pretty good that life didn't begin on this planet without outside influences:
QUOTE
The Cardiff team suggests that radioactive elements can keep water in liquid form in comet interiors for millions of years, making them potentially ideal "incubators" for early life. They also point out that the billions of comets in our solar system and across the galaxy contain far more clay than the early Earth did. The researchers calculate the odds of life starting on Earth rather than inside a comet at one trillion trillion (10 to the power of 24) to one against.
It sounds like something Spock would tell the captain!
http://www.sciencedaily.com/releases/2007/...70814093819.htm
