According to Matthew Hutson at Popular Mechanics, "5 Projects Ask if Life on Earth Began as Alien Life in Space" (December 16, 2008):For years, scientists have considered the possibility of exogenesis, the idea that life arrived on Earth from another planet, and not just the building blocks of life, but organisms that were ready to rock and roll when they arrived. It’s a Rube Goldberg scenario, however, dependent on several successful steps. First, life has to evolve on an alien planet. Then it must be blasted into space on a rock, probably from a large impact. Assuming it survives a long journey through harsh conditions—and makes its way into our neighborhood—life then has to resist fiery atmospheric entry and a brutal landing before trying to make a new home for itself.Five projects. I wonder if the ghost of Francis Crick is their patron saint? (The double helix guy believed, controversially, that life must have come from outer space.)
See also:
Origin of life: A meatier theory? Or just another theory?
Origin of life: There must be life out there vs. there can't be life out there
Origin of life: Oldest Earth rocks may show signs of life, in which case ...
Origin of life: Positive evidence of intelligent design?
Origin of life: But is being greedy enough?
Origin of life: Ah, that "just so happens" intermediate series of chemical steps
Why should the search for Darwin's "warm little puddle" be publicly funded?
(Note: The image of Crick is from Wikimedia Commons.)
