Continuing with this part #3 (see previous part #1 and part #2) of a series commenting on origin of life specialist John Keosian's paper "The Crisis in the Problem of the Origin of Life" (1978).
[Left: Svante August Arrhenius (1859-1927), Wikipedia]
Keosian gives "Extraterrestrial Origin of Life," i.e. Panspermia (both undirected and directed) short shrift, as "At best ... a retreat from the reality of the origin of life on Earth, or our ability to solve the problem in that context" and "a thinly-veiled justification for further costly space ventures" (my emphasis):
"Extraterrestrial Origin of Life CRICK and ORGEL [Crick, F.H.C. & Orgel, L.E., "Directed Panspermia," Icarus Vol. 19, 1973, p.341], suggested in 1973 that life may not have originated on Earth but was sent here long ago in the form of germinal material, from elsewhere in the universe. This hypothesis based on an old theory of panspermia proposed by ARRHENIUS in 1908 [Arrhenius, S., "Worlds in the Making," Harper & Brothers, New York, 1908], has been revised by the authors together with a rationale why any society might have considered such a course of action and why we, too, might consider it. SAGAN (1974) [Sagan, C., "The Origin of Life in a Cosmic Context," Origins of Life, Vol. 5, 1974, pp. 497-505] concedes that life could have originated on Earth but views our preoccupation with eking out the answer by getting to know more and more about what did happen here on Earth, as parochialism and provincialism. Sagan proposes that: `It is only the discovery and characterization of extraterrestrial life-even if very simple forms are found-which can deprovincialize biology.' At best, such suggestions represent a retreat from the reality of the origin of life on Earth, or our ability to solve the problem in that context. Such suggestions serve, also, as a thinly-veiled justification for further costly space ventures." (Keosian, J., "The Crisis in the Problem of the Origin of Life," in Noda, H., ed., "Origin of Life: Proceedings of the Second ISSOL Meeting, the Fifth ICOL Meeting," Center for Academic Publications: Japan, 1978, pp.569-574, p.570. Emphasis original).
Crick and Orgel in their 1973 Icarus paper make two major criticisms of undirected panspermia that: 1) even a "radiation resistant spore would receive so large a dose of radiation" that it would not "remain viable;" and 2) "The probability that sufficiently massive objects escape from a Solar System and arrive on the planet of another one is considered to be" too "small":
"Arrhenius (1908) proposed that spores had been driven here by the pressure of the light from the central star of another planetary system. His theory is known as Panspermia. Kelvin suggested that the first organisms reached the Earth in a meteorite. Neither of these theories is absurd, but both can be subjected to severe criticism. Sagan (Shklovski and Sagan, 1966; Sagan and Whitehall, 1973) has shown that any known type of radiation resistant spore would receive so large a dose of radiation during its journey to the Earth from another Solar System that it would be extremely unlikely to remain viable. The probability that sufficiently massive objects escape from a Solar System and arrive on the planet of another one is considered to be so small that it is unlikely that a single meteorite of extrasolar origin has ever reached the surface of the Earth (Sagan, private communication)." (Crick, F.H.C. & Orgel, L.E., "Directed Panspermia," Icarus, Vol. 19, 1973, pp.341-346, p.342. Emphasis original).
One only has to think of the probability that a dust grain with an embedded spore from Earth could find its way across light-years of interstellar space and land safely on an extrasolar Earth-like planet (which astronomers have yet to prove even exist), to realise the effective impossibility of the reverse happening, i.e. from an extrasolar planet to Earth. As microbiology professor Peter Sneath pointed out, "The most serious difficulty is that of space itself" because "Space is so vast that even if cubic miles of spores were liberated in it they would become so dispersed in the enormous volumes of space that there would be little chance that a planet such as the earth would ever capture any of them":
"The other alternative was most convincingly advocated by the great Swedish chemist S. Arrhenius, who called it the panspermia hypothesis. Arrhenius suggested that life arrived on the earth in the form of germs such as the spores of micro-organisms, and that these had been carried across the depths of space from elsewhere in the universe, propelled by the weak but continued pressure that is exerted by light rays on minute particles. ... Arrhenius showed theoretically that light pressure would be able to move small particles over very great distances. He also showed that violent volcanic eruptions might carry such particles into the stratosphere, from whence they might be driven into interplanetary space. He calculated that particles might reach the nearest stars, the Alpha-Centauri group, in some thousands of years. However, larger particles would tend to fall by gravitation into the sun. Arrhenius thought that the earth may have received its first life from spores transported from planets elsewhere in the universe, and believed that the extreme cold of outer space would not cause them to perish during their journey, nor would the transient heating as they entered the earth's atmosphere. Indeed there are many plausible arguments in the panspermia theory, and the astronomer Carl Sagan of Harvard University has re-examined many of these points. A spore of diameter 0.4 to 1.2 microns (1 micron = 1/1000th of a millimetre) is of the right size to be pushed out from the solar system by the sun's light. It would reach the orbit of Mars within a few weeks, and the nearest stars, as Arrhenius said, in some tens of thousands of years. A spore rather larger than this would be attracted to the sun (because for it the gravitational pull would be greater than the radiation pressure), and might hit the earth en route. Spores of quite a variety of sizes could be expelled from other planetary systems, depending on the mass and brightness of their suns. In outer space bacterial spores might survive for thousands or even millions of years, provided they had some protection against ionizing radiation, such as might be afforded by adsorbed dust particles. The most serious difficulty is that of space itself. Space is so vast that even if cubic miles of spores were liberated in it they would become so dispersed in the enormous volumes of space that there would be little chance that a planet such as the earth would ever capture any of them. In any case the great majority would be burned up by the stars or in hot gas clouds. Such calculations are necessarily speculative, but they would make it seem very improbable that life could have reached the earth from elsewhere. There may, however, be some possibility of transport from the earth to other planets in the solar system. Thomas Gold has suggested an alternative method of transport: the earth may once have been visited by an expedition from some advanced civilization elsewhere in our galaxy, and microbes may have been left behind!" (Sneath, P.H.A., "Planets and Life," The World of Science Library, Thames & Hudson: London, 1970, pp.74-75)
However, having rightly disposed of undirected panspermia, Crick and Orgel proposed "Directed Panspermia, the theory that organisms were deliberately transmitted to the earth by intelligent beings on another planet" (my emphasis):
"It now seems unlikely that extraterrestrial living organisms could have reached the earth either as spores driven by the radiation pressure from another star or as living organisms imbedded in a meteorite. As an alternative to these nineteenth-century mechanisms, we have considered Directed Panspermia, the theory that organisms were deliberately transmitted to the earth by intelligent beings on another planet. We conclude that it is possible that life reached the earth in this way, but that the scientific evidence is inadequate at the present time to say anything about the probability. We draw attention to the kinds of evidence that might throw additional light on the topic." (Crick & Orgel, 1973, p.341)
But apart from Keosian's criticisms above, directed panspermia has an additional problem in that it requires the time for: 1) life to spontaneously generate on at least one other planet; 2) evolve naturalistically into a technological civilisation; 3) that discovers that at least one other planet Earth is suitable for microorganisms to be seeded via a space probe; and 4) the probe to reach Earth and discharge its living cargo which took root on Earth before ~3.5 billion years ago.
Crick & Orgel make a fatal error in that they implicitly assume that the Universe "6.5 x 10^9 yr before the formation of our own Solar System," i.e. ~11 billion years ago, had the same life-permitting properties as the universe from 4.6 billion years to the present has:
"The local galactic system is estimated to be about 13 x 10^9 yr old (See Metz, 1972), The first generation of stars, because they were formed from light elements, are unlikely to have been accompanied by planets. However, some second generation stars not unlike the Sun must have formed within 2 x 10^9 yr of the origin of the galaxy (Blaauw and Schmidt, 1965). Thus it is quite probable that planets not unlike the Earth existed as much as 6.5 x 10^9 yr before the formation of our own Solar System. We know that not much more than 4 x 10^9 yr elapsed between the appearance of life on the Earth (wherever it came from) and the development of our own technological society. The time available makes it possible, therefore, that technological societies existed elsewhere in the galaxy even before the formation of the Earth. We should, therefore, consider a new `infective' theory, namely that a primitive form of life was deliberately planted on the Earth by a technologically advanced society on another planet." (Crick & Orgel, Ibid, p.342).
But since the Universe is expanding, at ~3 billion years old (as it was ~11 billion years ago, given that the age of the Universe is ~13.7 billion years) it would have been compressed into a volume of space much less than it was at ~10 billion years old when life began on Earth ~4 billion years ago. At ~3 billion years old, galaxies would have been much closer together and lethal radiation (including from black holes, quasars, supernovas and gamma ray bursts), more frequent and more energetic (and bearing in mind that radiation falls of by the square of the distance), with many radioactive elements still in their early half-lives.
As ID theorists astronomer Guillermo Gonzales and philosopher Jay Richards note in their book, "The Privileged Planet" (2004), "even if some stars had Earth-size planets only a few billion years after the beginning, they would have been stranded in the most dangerous neighborhoods. Unlike our present, the early universe was poor in heavy elements and rich in high-energy quasars, star births, and supernovae. Early-forming planets in the inner regions of galaxies would have been bathed in lethal levels of gamma ray, X-ray, and particle radiation" (my emphasis):
"We've discussed the Circumstellar Habitable Zone in our Solar System and the larger-scale Galactic Habitable Zone. But there's a still larger-scale framework, which we can call the Cosmic Habitable Age (CHA). When we consider the universal properties of the observable universe, age is more basic than location. Not all places and times around a star or within a spiral galaxy are equally habitable. Similarly, not all ages of the universe are equally habitable. This is obvious in the very early universe prior to decoupling. At that epoch the universe was a dense, hot plasma of elementary particles and light nuclei. Stars had not yet synthesized the heavy elements that make up our bodies. It was a dreadfully hostile environment for life of any sort. But the beginning is not the only no-man's land. If we think of everything an environment needs to support life, especially complex life, then, cosmically speaking, probably only a fairly short period in the history of the universe is habitable. The life-essential elements heavier than helium weren't present in the universe until they were made in the first stars and then ejected from their interiors. The first generation of stars began seeding their environment perhaps a few hundred million years after the beginning of cosmic time. The life-essential elements concentrated more quickly in the larger galaxies, especially in their inner regions. So even if some stars had Earth-size planets only a few billion years after the beginning, they would have been stranded in the most dangerous neighborhoods. Unlike our present, the early universe was poor in heavy elements and rich in high-energy quasars, star births, and supernovae. Early-forming planets in the inner regions of galaxies would have been bathed in lethal levels of gamma ray, X-ray, and particle radiation. ... In short, the universe has been getting more habitable." (Gonzalez, G. & Richards, J.W., "The Privileged Planet: How Our Place in the Cosmos is Designed For Discovery," Regnery: Washington DC, 2004, pp.181-182)
Moreover, even if life had been able to spontaneously generate and survive when the Universe was ~3 billion years old, as Gonzales & Richards point out, "when most of the stars in the Milky Way galaxy formed, hot dust blocked the view of the distant universe" so "if they could have existed, early cosmic residents might have enjoyed the show" (of "a spectacular fireworks display of nearby supernovae and quasars, their central black hole engines fed by abundant gas falling in toward their deep gravity wells" in "a young universe filled with distorted galaxies, disturbing one another through close encounters" and "intense heating from the many massive stars and supernovae"), "But they wouldn't have seen far beyond it" (my emphasis):
"As we gaze out into the distant universe, we now know we are peering back in time to an epoch close to the Big Bang event. We're inclined to marvel at the scientific ingenuity that has allowed us to decode such information. But we shouldn't forget the remarkable conditions necessary for such ingenuity. Our location in the Milky Way allows us to view the distant universe and also the many different kinds of nearby stars, a prerequisite for understanding other galaxies. But for scientific discovery, time may be as important as location at the largest scales. Hypothetical and bizarrely hearty residents of the early universe-say, a billion years or two billion after the beginning-would have had a front row seat to a spectacular fireworks display of nearby supernovae and quasars, their central black hole engines fed by abundant gas falling in toward their deep gravity wells. The Hubble Deep Fields reveal a young universe filled with distorted galaxies, disturbing one another through close encounters. Partly as a result, the intense heating from the many massive stars and supernovae bequeaths to the galactic dust a bright and sometimes beautiful glow. So when most of the stars in the Milky Way galaxy formed, hot dust blocked the view of the distant universe. If they could have existed, early cosmic residents might have enjoyed the show. But they wouldn't have seen far beyond it." (Gonzalez & Richards, 2004, pp.185-186)
and therefore they would not have been able to see other planets like Earth to send their microorganisms to!
The most significant thing about directed panspermia is that Crick, the co-discoverer of the structure of DNA and Orgel, one of the world's leading origin of life researchers, felt the need to propose it. As Keosian pointed out, "such suggestions represent a retreat from ... our ability to solve the problem in that context" of "the origin of life on Earth". On one of his tapes, Phillip E. Johnson rightly calls directed panspermia, "the materialists' version of supernatural creation"!
Immediately after Keosian's main critique of panspermia, he has a brief paragraph criticising a paper in the same ISSOL conference by University of Bradford chemists Jim Brooks and Gordon Shaw:
"A more recent argument for the extraterrestrial origin of life has been proposed by BROOKS and SHAW (1977) [Brooks, J. & Shaw, G.: 1977. Abstracts, Conference Program]. They have found materials closely related to sporopollenin in the oldest sediments. The authors make a number of controversial assumptions, thus jeopardizing their conclusion." (Keosian, 1978, p.570. Emphasis original).
which I may comment on when I finish Keosian's paper.
However, here is one notable quote from Brooks & Shaw's paper (which significantly Keosian did not disagree with), concluding that "there is no evidence that a `primeval soup' ever existed on this planet for any appreciable length of time" and "If we subtract the idea of a substantial amount of `primitive soup' and a long period of time from the basic concept of the Chemical Evolution Theory, there is very little left"!:
"On the contrary there is no evidence that a `primeval soup' ever existed on this planet for any appreciable length of time. If a `soup' had existed, the very basis of the Chemical Evolution Theory would require that it would have had to contain large quantities of nitrogen-containing organic compounds (amino acids. nucleic acid bases, etc.). Such materials in laboratory experiments are readily absorbed on sedimentary inorganic particles and would therefore under normal geological conditions and in an environment that did not contain life unquestionably sediment along with the rock and mineral particles. The result of this should have been the formation of vast areas of sediments containing organic compounds-since the theories of Chemical Evolution demand that large quantities of such compounds should occur over long periods of time, so that chance might have an opportunity to exert its influence on the various chemical processes which are assumed to have led to a living system. It would of course be inevitable that such sediments would undergo normal diagenetic processes when we would then expect to find significant quantities of `nitrogenous- cokes,' trapped in various sediments. The formation of such `cokes' is the normal result obtained by heating organic matter rich in nitrogenous substances. No such materials have yet been found in Precambrian rocks on this planet. In fact the opposite seems to be the case. The nitrogen content of Precambrian organic matter is exceptionally low (<0.2%). The insoluble organic matter (`kerogen') present in Precambrian sediments generally contains largely carbon, hydrogen, and oxygen with very little organic nitrogen or sulphur. We can therefore conclude with some degree of certainty that: a) There never was any substantial amount of `primitive soup' on Earth when ancient Precambrian sediments were formed; and that b) If such a `soup' existed it was only for a brief period of time. If we subtract the idea of a substantial amount of `primitive soup' and a long period of time from the basic concept of the Chemical Evolution Theory, there is very little left." (Brooks, J. & Shaw, G., "A Critical Assessment of the Origin of Life," in Noda, H., ed., "Origin of Life: Proceedings of the Second ISSOL Meeting, the Fifth ICOL Meeting," Center for Academic Publications: Japan, 1978, pp.597-606, p.604)
Brooks is a Christian (I don't know about Shaw) and he has some interesting things to say about Christianity and the origin of life in a Christian book of his, Brooks J., "Origins of Life," Lion: Tring, Hertfordshire UK, 1985. I have also ordered Brooks & Shaw's book, "Origin and Development of Living Systems" (1973) which I may quote from when I get to their paper.
Continued in part #4.
Stephen E. Jones, BSc. (Biology).
Exodus 3:16-22. 16"Go, assemble the elders of Israel and say to them, 'The LORD, the God of your fathers - the God of Abraham, Isaac and Jacob - appeared to me and said: I have watched over you and have seen what has been done to you in Egypt. 17And I have promised to bring you up out of your misery in Egypt into the land of the Canaanites, Hittites, Amorites, Perizzites, Hivites and Jebusites - a land flowing with milk and honey.' 18"The elders of Israel will listen to you. Then you and the elders are to go to the king of Egypt and say to him, 'The LORD, the God of the Hebrews, has met with us. Let us take a three-day journey into the desert to offer sacrifices to the LORD our God.' 19But I know that the king of Egypt will not let you go unless a mighty hand compels him. 20So I will stretch out my hand and strike the Egyptians with all the wonders that I will perform among them. After that, he will let you go. 21"And I will make the Egyptians favorably disposed toward this people, so that when you leave you will not go empty-handed. 22Every woman is to ask her neighbor and any woman living in her house for articles of silver and gold and for clothing, which you will put on your sons and daughters. And so you will plunder the Egyptians."
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