I've been reading about panspermia for some time and its a beautiful theory which slots well with emerging biotechnological discoveries. Heres a little background.
As extremophile indicates, in essence the major part of panspermia is the view that life is a natural consequence of the way the universe is "constructed" and works. By accident, or design, the universe has a very strong tendancy to "create/make" life's molecules and structures, almost as if it were a natural PROCESS of cosmic evolution.
One major breakthrough to this idea, discovered by which Chandler Wickramasigne, was the discovery of organic molecule absorbtion patterns of interstellar dust. Later they found absorption patterns in interstellar dust that match, near perfectly, that of dried bacteria (
Analysis of Interstellar Dust and Selected Resources. by Brig Klyce). So somehow interstellar dust is riddled with bateria and organic molecules, almost as if life is everywhere! (i know your question, wait ;-)
If one can accept the above as being a possibility, then it is not difficult to see how Earth could be seeded with life from space (and is STILL BEING SEEDED from space to this day!)
Indeed, imagine for a moment, our young star systems gas cloud was "seeded" with lifes molecules (chloroplasts, nucleiotides, etc) and bateria and inorganic molecules before its birth. During the condensation of the gas/molecular/baterial clouds into our star systems, organic and inorganic molecules would form part of the composition of all planets, comets & moons. So the molecules of life and bateria where already here at the beginning. This would help to account for lifes abundant ecosystems found kilometers below earths surface which has not had exposure to the surface. It would also help to explain why comets and meteorites have an abundance of organic compounds.
The questions of how/where did life originate, what processes go into the creation of organic compounds and cells still remains. I remember two aspects of their and associated works which get us closer to answering these questions. 1) That comets provide an excellent environment for concentrated and complex chemical reactions to take place (a sort of primordial soup), 2) the corona of stars facilitates the joining of molecules to create complex organic compounds such as chlorophyll. If you would like clearies theories visit the website or read some other books it suggests.
The website
COSMIC ANCESTRY: Panspermia's evidence and implications. and articles and books by Hoyle and Wickramasinghe go into a lot more detail, such as;
* lifes use of viruses for the transfer of genes between speicies (horizontal transfer),
* gene transfer as the major evolutionary force, transfering large chunks of DNA/RNA from one organism to another,
* desease outbreaks coinsiding with Earths passage through a comet's path, evidence of comets as a vector of biological information (a.k.a viruses/bacteria)
* natural selection as a fine tuning mechnism for activated genes,
* evolution through genetic mutation being VERY improbable,
* Panspermia as an interesting new light on Creationism,
* Its not a matter of how life originated, but where life will originate again!
Their mission, so to say, is not to provide an answer to the origins of life, but to instigate a paradigm shift away from the Earth-centric Darwinian perspective, to a more universal, inclusive, *open ended* view of lifes origins and its existance. Thanks to biotechnological advances and techniques, comet sampling satalites, space telescopes, mars rovers etc, their theory looks more and more accurate as the weeks pass!
I could rant on but I need a break ;-) What are you thoughts? Especially I ask those who've read some of their material (ie, at least
COSMIC ANCESTRY: Panspermia's evidence and implications. if not a book or two)
Sean