T. Peter Park
Thu, 26 May 2005 08:17:35 -0700
N.B.--If Chandra Wickramasinghe and Fred Hoyle are right, and Earth (and other planets throughout the Universe) were "seeded" with life from interstellar dust-clouds, then all life throughout the Universe may be basically very similar, though of course showing the range of outward variation we see on Earth between bacteria, amoebae, mushrooms, seaweeds, Sequoia trees, sponges, jellyfish, ants, clams, starfish, sharks, lizards, penguins, cats, mice, and humans, or, as science-fiction writer Poul Anderson once put it, between moose and tobacco plants, pigs and petunias--T.P.P. Are We Seeded From Stardust? Panspermia: An Interview with Professor Chandra Wickramasinghe Dateline: Wednesday, May 25, 2005 By: STUART MILLER By Phenomena News Editor Chandra Wickramasinghe (CW) is acknowledged as being one of the world's leading experts on interstellar material. He is an award-winning poet and the author of over 25 books and over 350 scientific papers. His work on the Origins of Life and the theory of Panspermia is coming to be recognized as one of the most important developments in science in recent years. He is interviewed by Stuart Mller (SM), editor of UFO Review and Phenomena News Editor. *** SM: Do you prefer to refer to it as the theory of Panspermia or as Cosmic Ancestry? CW: Panspermia is a rather hackneyed description of the idea that Life can be transferred from one part of the Universe to another. It is probably more easily recognised and understood than Cosmic Ancestry, I would have thought. But I have no strong opinions either way. SM: What made Sir Fred Hoyle and you go back to it, because it is a theory that in one shape or form or another has been around for a very long time. What brought the two of you back to look at it? CW: It's a very long story in fact and begins with my work with Sir Fred Hoyle on the nature of interstellar and cometry dust. I began my PhD work on the chemisty and composition of cosmic dust way back in 1962 and at the time, the idea that was really well entrenched in the astronomical community was that the dust in space, the dust that you see in all the dark clouds of interstellar space, was mainly comprised of tiny, sub micron sized ice particles, similar to the particles that are present in the cumulous clouds in the Earth's atmosphere. When we examined all the literature on the subject, it turned out that the whole question of how ice particles condensed in the interstellar clouds was not properly addressed in terms of mathematics and physics. We know that clouds, even in the earth's atmosphere, could be highly super-saturated with respect to water, but droplets or particles of ice do not form unless there exist what are called condensation nuclei. There's got to form charged molecular aggregates at an adequate rate around which saturated water molecules could condense. When we examined well-established theories of nucleation and applied them in a cosmic context, it turned out there was no easy way to overcome the nucleation hurdle. You have interstellar clouds that are highly saturated in water vapour, but they wouldn't form particles of ice, the reason being that the clouds are exceedingly tenuous. There's one hydrogen atom per cubic centimetre or something like that. Under those conditions, we reckoned that particles do not form. So we had to go to denser places in order to form interstellar dust particles, and the first place we looked at were the atmospheres of cool stars. And a group of cool giant stars known as the carbon stars were the location we chose for our first investigation of where dust might form. SM: Why did you go to cool stars to solve the problem of dust formation? CW: Because the interstellar condensation process seemed to be totally inadequate, woefully inadequate to form solid particles out of a pure gas. So going to the carbo- rich cool stars provided us with an alternative location in which the nucleation/condensation processes could occur. The consequence is that if you go to such stars, the dust particles that form must be made of carbon, not water-ice. For about a decade we developed this theory and worked on the idea that the dust in space was made largely of the element carbon, possibly in the form of soot-like particles, polycrystalline graphite. But towards the end of the 1960s, with new developments in observational astronomy, there were new techniques for looking more deeply at the nature of interstellar dust. We found that dust made of soot-like graphite was not completely adequate to meet up with the new constraints, particularly at infrared wavelengths, and we had to then develop the theory of organic grains, carbon in the form of organic polymers. So that was really the starting point of the idea that molecules in interstellar space were organic and could be connected with Life. Over the period from 1970 to 1979, the dust particles we were looking at turned out to be not simply organic, but exceedingly complex in their organic nature. Eventually it turned out that they had to match the properties of a freeze-dried bacterium to an uncanny degree of precision. It didn't mean that the particles had to be bacteria necessarily, but they had to be of a chemical composition that matched the spectrum of a bacterium, in the infrared and ultraviolet wavebands. Moreover, a third of all the carbon in interstellar space had to be of this form. That is to say, it was tied up in the form of particles that are indistinguishable from bacteria by every remote-sensing criterion that we could think of. How could such a situation arise? It was at this point that we began to look seriously at the old theories of how Life started on the earth. We concluded before long that there was no firm evidence to regard these ideas as a proven fact - that Life started on the Earth. The fact that Life exists on the Earth does not mean that Life started on the Earth. We made several analogies to illustrate the point. For example, the Celtic languages are spoken in Wales but it didn't originate from Wales. They came from mainland Europe many thousands of years ago. So the fact that Life exists does not mean that Life started on the Earth. When we examined the probabilities that are involved in putting together the most primitive living system, for instance, considering how amino acids combine into a basic set of enzymes (that is crucial for life), it didn't take a lot of calculation to discover that this is an incredibly improbable event. If it happened on the Earth, it means we've essentially overcome superastronomical odds in doing so. In view of the superastronomically vast improbability factors that are associated with the assembly of the first living system, we quickly rejected the Earth as a reasonable site for a first origin of life. It would obviously pay to go to the biggest available cosmic system if one had to overcome such incredible odds. And the biggest available cosmic system is the Universe as a whole. The transition from non-life to life in our view must have involved the resources of all the stars in all the galaxies in a substantial part of the Universe, but this transformation needs to have taken place only once. The Earth is of course not a closed system. The Earth receives debris from comets, hundreds of tons of cometry debris, much of which is known to be organic, enters the Earth's atmosphere on a daily basis. The solar system itself, the comets being part of the solar system, is connected to interstellar clouds, for the simple reason that it condensed and formed from such a cloud. S! o there's a physical connection that extends from the Earth all the way to the formation of the solar system, the formation of the galaxy, and maybe to the formation of clusters of galaxies. That was the thinking behind the revival of the ancient theory of Panspermia. SM: You had very little support at all when this came out. How much opposition did you get? More- Panspermia: are we seeded from star dust? <http://www.phenomenamagazine.com/0/editorial.asp?aff_id=0&this_cat=Area+51&action=page&obj_id=3290&type_id=3&cat_id=132&sub_id=0> http://www.phenomenamagazine.com/0/editorial.asp?aff_id=0&this_cat=Area+51&action=page&obj_id=3290&type_ <http://www.phenomenamagazine.com/0/editorial.asp?aff_id=0&this_cat=Area+51&action=page&obj_id=3290&type_> id=3&cat_id=132&sub_id=0 > [Non-text portions of this message have been removed] ------------------------ Yahoo! Groups Sponsor --------------------~--> In low income neighborhoods, 84% do not own computers. 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