A new study supported by the NASA Astrobiology Institute suggests that the possibility of life being transferred from the inner solar system to the moons of Jupiter and Saturn, although very rare, cannot be ruled out.
The idea that life can spread through space is known as panspermia. One class of panspermia is lithopanspermia -- the notion that life might travel on rocks knocked off a world's surface. If these meteoroids encase hardy enough organisms, they could seed life on another planet or moon.
Although lithopanspermia might seem farfetched, a number of meteorite discoveries suggest it might at least be possible. For instance, more than 100 meteorites originating from Mars have been discovered on Earth, blasted off the red planet by meteor strikes and eventually crashing here.
"There have been previous simulations looking at transfer between Earth and Mars, but we wanted to scale the simulations up in the hopes of seeing transfer to Jupiter and Saturn," said study lead author Rachel Worth, an astrophysicist at Pennsylvania State University.
The paper, "Seeding Life on the Moons of the Outer Planets via Lithopanspermia ," was published in the journal Astrobiology. http://online.liebertpub.com/doi/abs/10.1089/ast.2013.1028
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