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Scientists Offer 'Overwhelming' Evidence Terran Life Began in Space 556

Posted by Zonk
from the we-are-all-made-of-stardust dept.
An anonymous reader writes "Using data from recent comet-probing space missions, British scientists are reporting today that the odds of life starting on Earth rather than inside a comet are one trillion trillion (10 to the power of 24) to one against. That is, we're not originally from around here. Radiation in comets could keep water in liquid form for millions of years, they say, which along with the clay and organic molecules found on-board would provide an ideal incubator. 'Professor Wickramasinghe said: "The findings of the comet missions, which surprised many, strengthen the argument for panspermia. We now have a mechanism for how it could have happened. All the necessary elements - clay, organic molecules and water - are there. The longer time scale and the greater mass of comets make it overwhelmingly more likely that life began in space than on earth."'" jamie points out that the author of this paper has many 'fringe' theories. Your mileage may vary.
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Scientists Offer 'Overwhelming' Evidence Terran Life Began in Space

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  • by Anonymous Coward on Tuesday August 14, 2007 @02:24PM (#20227651)
    That's where God lives.
  • No kidding (Score:5, Funny)

    by eln (21727) * on Tuesday August 14, 2007 @02:24PM (#20227655) Homepage
    The great anthropologist Dr. Douglas Adams already showed that we did not originate here. In fact, we were passengers on the 'B' Ark that crash-landed here. Our ancestors come from an ancient civilization called Golgafrinchans. It is a shame that Dr. Adams's work is so widely ridiculed as a "humorous" bit of "fiction" in wider scientific circles.
    • by MorderVonAllem (931645) on Tuesday August 14, 2007 @02:29PM (#20227745)
      Well, if we take him serious then we might have to take hubbard serious.
      • Re:No kidding (Score:5, Insightful)

        by Sunburnt (890890) * on Tuesday August 14, 2007 @02:48PM (#20228075)

        Hardly. Adams' writings are more consistent, structured, and believable than Hubbard's.

        Also, it helps that Douglas Adams wasn't a complete batshit loon.

        • Re:No kidding (Score:5, Insightful)

          by meringuoid (568297) on Tuesday August 14, 2007 @03:32PM (#20228821)
          Hardly. Adams' writings are more consistent, structured, and believable than Hubbard's.

          What nonsense. Adams changed the whole story substantially every few years. The radio told one story, then the record told another, then the books told yet another, and then there was the other version of which we do not speak for horror at the memory of the Babel Fish Puzzle, and then there was the TV series...

          Oh wait, hang on. That only qualifies the saga all the more for religious status :-)

    • by Fozzyuw (950608)
      You know, I remember reading the book, but I don't remember the ending. However, I did finish the BBC series on this.

      According to the BBC series, Arthur Dent and Ford Prefect where on the 'B' Arc that crashed on earth as well as there already having been 'cavemen' on earth at the time of the crash.

      Thus, it's inconclusive that life came from the 'B' Arc. Bath anyone?

      • by dpilot (134227)
        Now that you mention it, Arthur was able to query the 'cavemen' about the Super-Deep-Thought question. So it just might be apparent that the Golgrafinchians died out. (Couldn't figure out how to reproduce, perhaps.)
  • Obligatory (Score:5, Funny)

    by RealErmine (621439) <commerce@NOSPAM.wordhole.net> on Tuesday August 14, 2007 @02:24PM (#20227659)
    I for one welcome... uh, myself.
  • hm.. (Score:5, Insightful)

    by UncleWilly (1128141) * <UncleWilly07.gmail@com> on Tuesday August 14, 2007 @02:24PM (#20227663)
    In a manner of speaking, didn't everything start in space?
  • by BobPaul (710574) * on Tuesday August 14, 2007 @02:24PM (#20227673) Journal
    In an ironic statement, they also claim Protoss life began on Earth...
  • by Overzeetop (214511) on Tuesday August 14, 2007 @02:25PM (#20227675) Journal
    There was never a better time to tag a story nevertellmetheodds!
  • Others? (Score:3, Interesting)

    by Turn-X Alphonse (789240) on Tuesday August 14, 2007 @02:25PM (#20227677) Journal
    This makes me wonder if there are other mobile space entities smaller than planets which harbor our earlier form of life. It seems extremely unlikely it was just once and the random chance it hit Earth seems far far too unlikely. So should we be looking at things smaller than planets for life or keep searching how we are now?
    • Re: (Score:3, Interesting)

      by eln (21727) *
      I'm pretty sure we've already sent probes out to asteroids, but I don't know if they were capable of detecting organic compounds or if they were only looking for water.

      For stuff outside of our own solar system, I think right now we're only just beginning to learn how to detect planets smaller than Jupiter, so finding an object smaller than a planet that far out is probably beyond our capabilities at the moment.

      Even so, if you're looking for really complex life (such as intelligent life), you'd be better ser
      • Re: (Score:3, Interesting)

        by marcosdumay (620877)

        "I'm pretty sure we've already sent probes out to asteroids, but I don't know if they were capable of detecting organic compounds or if they were only looking for water."

        Organic compounds are everywhere at the Solar System. It is so easy to detect them at dust released by commets or at surfaces that it doesn't make even news anymore.

  • by rhombic (140326) on Tuesday August 14, 2007 @02:25PM (#20227681)
    Soooooo, they used two numbers (mass of clay & # of comets) to generate a 1e24 to 1 odd against life having started here? Seems like they might have left one or two variables out of their equation. Hopefully this is just junk reporting rather than junk science.

    • Yeah, I'm curious how they came up with that number. Is that number of water bearing radioactive clay infused comets with enough mass to get early life down to an ocean they think are in our general area or something? I have to admit, both my Junk Science and Junk Reporting needles are hovering on the redzone right now.
    • by MightyMartian (840721) on Tuesday August 14, 2007 @02:32PM (#20227811) Journal
      It's much worse than that. Like all panspermia advocates, and like a good many Creationists, they essentially crib the "odds" argument. This looks no different than any other pro-panspermia "study" in that it starts with a strawman of abiogenesis.
      • I don't understand. I just looked up abiogenesis and the word just means life from non-living matter. By definition doesn't that have to be the start of any theory of life evolving? I'm not sure why you called it a strawman.
        • Re: (Score:3, Interesting)

          by MightyMartian (840721)
          The strawman lies in the claim that current abiogenesis theories don't give enough time for the kind of organic chemical evolution that would lead to the earliest metabolizing self-replicating molecules.
      • Right and wrong (Score:4, Insightful)

        by RealProgrammer (723725) on Tuesday August 14, 2007 @04:12PM (#20229329) Homepage Journal
        Or perhaps it depends on how you look at it. But the problem is easier to understand as a False Dilemma, not a Straw Man. Since we don't know exactly how long life takes to evolve, because it's a random process that we've never watched happen, it could be that it evolved independently on Earth, in comets, and all over the place. It could also have come solely from the planet Krypton. Even finding actual life in a comet would not show that it evolved there, rather evolving or being created by God on Krypton. That's a metaphor.

        The good professors should embrace, as they say, the healing power of 'and'.
      • by Hatta (162192) on Tuesday August 14, 2007 @04:32PM (#20229609) Journal
        I never got why panspermia was such a compelling theory. It just pushes the real question, "how did life begin", back a little. Maybe life on earth started from genetic material on a comet. That genetic material had to come from somewhere, so that just means that abiogenesis occurred on a planet other than earth. Why is abiogenesis elsewhere more likely than abiogenesis here?
        • by ultranova (717540) on Tuesday August 14, 2007 @06:00PM (#20230599)

          I never got why panspermia was such a compelling theory. It just pushes the real question, "how did life begin", back a little.

          The conditions of early Earth can be determined to some degree, and the time between Earth forming and the earliest known signs of life can also be determined. Any theory which states that life began on Earth has to explain how said conditions lead to life in said timeframe. This far none has.

          Panspermia, on the other hand, claims that life was born somewhere else at some point after the Big Bang and earliest signs of life on Earth. "Somewhere else" doesn't constrain the possible set of circumstances nearly as much as "on Earth", and the timeframe is far longer too. It is also impossible to prove false.

          Given the choice between lots of time-consuming chemistry reasearch and a hypothesis which is impossible to falsify or really even research but allows a lot of poetic pseudo-philosophical nonsense in the vein of "we are children of the stars", "cosmic bortherhood", and "the thrut is out there", which do you think people will choose ?

          • by Hatta (162192) on Tuesday August 14, 2007 @07:01PM (#20231177) Journal
            Any theory which states that life began on Earth has to explain how said conditions lead to life in said timeframe. This far none has.

            Except that it doesn't really. If the timeframe Earth has been around is 1/1000th of the average time you'd expect the abiogenetic process to yeild life on average, well that's ok. There are likely to be 1000s of Earth-like planets in the galaxy. All those stochastic molecular events are not only taking place on the surface of primative earth, but every other primative earthlike planet in the universe. It only has to happen once for us to be here and puzzle at how rare we are. I mean, the chances of winning the lottery are extremely low, but someone usually wins.

            Given the choice between lots of time-consuming chemistry reasearch and a hypothesis which is impossible to falsify or really even research but allows a lot of poetic pseudo-philosophical nonsense in the vein of "we are children of the stars", "cosmic bortherhood", and "the thrut is out there", which do you think people will choose ?

            You are right there. No doubt about it.
    • Re: (Score:2, Funny)

      by tillerman35 (763054)
      I think length of time was factored in somehow, the gist of it being that comets have been around a lot longer than the Earth and therefore more likely to have had the incubating effect.

      That stated, it'll take more than a few numbers in a formula to convince me. I'm not going to believe this until a cometary probe comes back contaminated with an alien microbe that destroys all life on the planet. And even then, I'll be a little bit skeptical.
    • by FuzzyDaddy (584528) on Tuesday August 14, 2007 @02:35PM (#20227855) Journal
      The odds are 1 in 10^24 if their assumptions are true... The odds of the assumptions being true is a different story.

      When I was in grad school our group was trying to make a particular type of superconducting circuit. After many attempts we got one that worked, wrote it up, and presented it at a conference.

      During the Q&A, someone asked my advisor what our yields were. "On a good day, 100%". The followup question was, "what's your yield on good days?"

    • by Phanatic1a (413374) on Tuesday August 14, 2007 @02:35PM (#20227859)
      It's junk science. Wickramasinghe and Hoyle are the same two who concocted the absurd probabilistic "tornado in a junkyard" argument against evolution. Hell, during the SARS outbreak, Wickramasinghe suggested that SARS was an alien virus. Yep, it just happened to have a sequence remarkably similar to other earth-borne viruses, and just happened to fall to earth in a region where similar viruses infected wild animals. Yep, that's the ticket.

      Hoyle at least used to be a real scientist. I'm not sure if Wickramasinghe ever was. He said "
      "The chances that life just occurred are about as unlikely as a typhoon blowing through a junkyard and constructing a Boeing 747" in 1982, so he's been a crackpot for a long time. This guy's just one step less crazy than Behe and the other 'intelligent design' crackpots. The only difference is that the intelligent designer posited by Wickramasinghe and Hoyle is a natural one, not a supernatural one; all the other problems with their claims are the same.
      • by UdoKeir (239957) on Tuesday August 14, 2007 @02:52PM (#20228155)
        I had Prof. Wickramasinghe was one of my Pure Maths lecturers during my first year at Cardiff. He was dreadfully hard to understand.

        My flatmate, who was a paleobotany postgrad at the time, had some very disparaging things to say about him. He had co-authored a few papers claiming the Archaeopteryx was a hoax, based on his poor understanding of the subject matter.

        http://en.wikipedia.org/wiki/Archaeopteryx#Authent icity [wikipedia.org]
      • by Bombula (670389) on Tuesday August 14, 2007 @02:54PM (#20228197)
        MOD PARENT UP - INFORMATIVE.

        For those interested in why the tornado in a junkyard assembling a 747 is a useless analogy for the process of evolution, the simple explanation is that evolution works by a ratcheting effect: improvements are made one tiny step at a time, in sequence, for a cumulative effect of complexity. The selection process by which those steps are made - i.e. mutations that constitute an improvement in fitness survive and others die out - is simple and nonrandom. The tornado analogy implies instant emergence of full complexity, which is nothing at all like what actually happens.

      • by MightyMartian (840721) on Tuesday August 14, 2007 @02:55PM (#20228203) Journal
        Hoyle's failure was an example of the classic trap that experts fall into. That is that as long as they stay in their own field of knowledge, they tend to be reliable, but the moment they move into another field where their knowledge is, at best, that of a layman, they get themselves into trouble. Unfortunately, scientists like Hoyle can get a lot of mileage by the mere fact that they are experts in some field of inquiry. He was a famous scientist, and when a famous scientist speaks, even when he's right out of his league, people tend to listen.
    • by Mr. Underbridge (666784) on Tuesday August 14, 2007 @02:40PM (#20227957)

      Soooooo, they used two numbers (mass of clay & # of comets) to generate a 1e24 to 1 odd against life having started here? Seems like they might have left one or two variables out of their equation. Hopefully this is just junk reporting rather than junk science.

      I have a new meta-theory for these sorts of things: if your hypothesis sounds like the Chewbacca Defense, it's almost certainly bogus.

    • by SpinyNorman (33776) on Tuesday August 14, 2007 @02:41PM (#20227973)
      Bear in mind that this self-validating conclusion comes from Professor Chandra Wickramasinghe who is intimately tied to the theory of panspermia. Let's wait for science to do it's thing and see if everyone else agrees with his conclusions and math (yeah, right)...

      Gotta say that last time I checked the water is liquid right here on planet earth also.
    • by snarkh (118018) on Tuesday August 14, 2007 @03:13PM (#20228521)

      Coming up with such a precise number seems particularly brilliant, considering that we have no
      idea how life really originated.
  • I have not RTFA but those are some humongous odds against based on the world "could". I guess I should RTFA then...

    • Re: (Score:3, Informative)

      by Shabbs (11692)
      Well, after I RTFA, the article does not even use the word "could" in that reference. Bad summary. The relevant quote is here:

      The Cardiff team suggests that radioactive elements can keep water in liquid form in comet interiors for millions of years, making them potentially ideal "incubators" for early life.
      Cheers.
  • So what they are saying we are the product of intergalactic sperm that fertilized this ovum we call earth. Maybe we aren't inside a giant snow globe but a giant uterus and when it contracts our universe will come to a sudden and brutal end.
    • Re: (Score:3, Funny)

      by superstick58 (809423)
      No, our universe will not end. We are the embryonic stem cells of the earth embryo. However, we will soon be harvested by the universe entity to be used to find a cure for galactic cancer. Unless the multi-verse government can pass the cosmos-bill banning earth-embryonic stem cell research, we are all doomed.
  • Yeah right (Score:5, Insightful)

    by bytesex (112972) on Tuesday August 14, 2007 @02:29PM (#20227737) Homepage
    So the odds of a combination of clay + radiation was only to be found inside comets and the chances of that surviving a fiery impact at many kilometers per second are _higher_ than the same combination occurring naturally, peacefully, here on earth ? Somehow my bullshit meter goes all bananas.
  • So complex biomolecules wanted to self-organize and replicate bathed in the warm glow of cosmic rays and accelerated protons and electrons, cooled gently to 3 deg Kelvin on some comet rather than in a musty old pool of water covered with deadly oxygen and unbreathable nitrogen here on boring old Earth?

    • by MightyMartian (840721) on Tuesday August 14, 2007 @03:01PM (#20228313) Journal
      Except that when life first evolved on Earth, there was no free oxygen in the atmosphere. In fact, the introduction of oxygen from cyanobacteria lead to the so-called oxygen catastrophe [wikipedia.org].
  • by 140Mandak262Jamuna (970587) on Tuesday August 14, 2007 @02:29PM (#20227759) Journal
    Even if the claim is true, we are just transferring the problem from how life originated on Earth? to How life originated in the universe?.

    Please before you mod me troll, listen. The Theory of evolution does not explain the origin of life, just the origin of species. Most folk who believe in things like ID (I= intelligent or idiotic depending on your perspective) confuse the issue and attack science. Let us not make the same mistake on the science side. Even the most ardent supporters of the Theory of evolution, like Dawkins, have only proposed very tentative speculation about the origin of life. They readily admit that right now science does not have any definitive theories about the Origin of Life.

    This has nothing to do with evolution. Let us keep the discussions straight.

    • Even if the claim is true, we are just transferring the problem from how life originated on Earth? to How life originated in the universe?.

      That makes a big difference, though. It's a question of probability. If life cannot spread through space, then it must have begun here of its own accord, and so we're looking for a theory that allows good odds that life will start on any planet chemically and environmentally favourable for it to do so. If life, once started somewhere in the Universe, can spread through

      • Re: (Score:3, Insightful)

        by DerekLyons (302214)

        Even if the claim is true, we are just transferring the problem from how life originated on Earth? to How life originated in the universe?.

        That makes a big difference, though. It's a question of probability. If life cannot spread through space, then it must have begun here of its own accord, and so we're looking for a theory that allows good odds that life will start on any planet chemically and environmentally favourable for it to do so.

        That's the trick though - you don't actually need good odds at all.

  • Huh? (Score:5, Funny)

    by Otter (3800) on Tuesday August 14, 2007 @02:32PM (#20227807) Journal
    The Cardiff team suggests that radioactive elements can keep water in liquid form in comet interiors for millions of years...

    Is there any evidence that comets have such isotopes at such concentrations? This sounds like the sort of thing Lex Luthor would be involved in.

  • We're not alone (Score:4, Interesting)

    by Ckwop (707653) * <Simon.Johnson@gmail.com> on Tuesday August 14, 2007 @02:32PM (#20227815) Homepage

    British scientists are reporting today that the odds of life starting on Earth rather than inside a comet are one trillion trillion (10 to the power of 24) to one against.

    It's probably also worth pointing out that this result has probably increased the chance of life existing elsewhere in the universe by a similar amount. There are far more commets than planet and they are a truly huge number of stars.

    Moreover, it is more plausible that a comet could fertilize many star systems if it was knocked out of the orbit of various stars in its life-time. While this sort of event is in itself unlikely it is orders of magnitude more likely than life being liberated from a planet from a violent impact. The life would have to survive the fiery, high G, exit from whatever atmosphere there was surrounding the planet and would still have to have sufficient momentum to escape the star. These properties taken together pretty much eliminate any chance of that happening.

    Compare this to the following comet hypothesis. Life gets started on a comet with a highly elliptical orbit billions of years ago. How this happens is open question but for the moment assume it does. As the star uses up its fuel it loses mass and the orbit slowly stretches. Eventually, the comet is able to free itself from the gravity of the parent star. Hundred of millions of years later, the star goes supernova. The blast wave from the supernova gently accelerates the comet into a planetary nebular. It just happens to be the one that our Earth was forged in. As the nebular condenses the life that started inside the comet transfers itself to the billions of water droplets and mineral material. You can guess what happens next.

    I've always suspected we are not alone. It's just whether we're all too far away from each other for the knowledge to make any difference.

    Simon

  • by First Person (51018) on Tuesday August 14, 2007 @02:36PM (#20227863)

    If I understand their argument correctly, the abundance of clay in certain comets provides the template for RNA formation and eventual RNA-based life (with DNA coming later). There may be other factors which are discussed in the actual paper. As such, consider these thoughts preliminary.

    There are several factors that would seem to argue against life starting in comets. First of all, planets have a far greater volume than comets with larger and more diverse areas in which life might form. Comets must not only reach planets but deliver their biologics intact. These biologics must then be suitable for propagation in the environment in which they arrive.

    That last point is quite important. If comets did provide a birthplace for life, it is quite likely that their cargo would be unable to survive such an abrupt transition. Far more likely is that the life started on the planet in the first place.

  • ... without a galactic space bookie? I'm feelin' lucky!
  • want to tell us that life was created by random comet falls?

    i demand equal time for the godly and righteous theory of intelligent comet placing!

    comets did not just fall randomly to earth and create life!

    god himself intelligently directed comets to come to the early lifeless earth 6,000 years ago!
    • Re: (Score:3, Funny)

      by Himring (646324)
      Kevin: Who was that man?
      Fidgit: That was no man. That was the Supreme Being.
      Kevin: You mean God?
      Fidgit: Well, we don't know Him that well. We only work for Him.
      Randall: Shut up!
      --Time Bandits

  • Sheesh (Score:5, Insightful)

    by Reality Master 101 (179095) <RealityMaster101@NOSpam.gmail.com> on Tuesday August 14, 2007 @02:38PM (#20227917) Homepage Journal

    British scientists are reporting today that the odds of life starting on Earth rather than inside a comet are one trillion trillion (10 to the power of 24) to one against.

    That they can even presume to put a number on the probability of life is evidence enough that they have no idea what they're talking about.

    Anyway, the odds of life are totally irrelevent to anything. See: anthropic principle.

  • Is this surprising? I mean, in the seventies it was a popular theory that life here began out there [wikipedia.org].
  • by oskay (932940) * on Tuesday August 14, 2007 @02:41PM (#20227963) Homepage
    Also in the news this week is the opposite result: that life cannot [theage.com.au] exist in comets because of the radiation. So... it's not obvious (to me) that there is any scientific consensus on this topic.
  • So a comet brought us into existence, and it could take us out of existence. Seems fair to me.
  • Edumakation (Score:3, Funny)

    by Shadow Wrought (586631) * <shadow...wrought@@@gmail...com> on Tuesday August 14, 2007 @02:44PM (#20228023) Homepage Journal
    If the Religious Right takes issue with Evolution, just wait they find out that little Bobby is going to be taught about Panspermia! In school! Next thing you know Health class will be teaching kids the proper way to masticate.
  • by RyanFenton (230700) on Tuesday August 14, 2007 @02:48PM (#20228079)
    we-are-all-made-of-stardust dept... close, but Sagan's line ended with 'star stuff', which is actually more appropriate here.

    As to the relative plausibility of comet-seeded or locally-formed progenitors to life, given that reactions propagate, commonly leading to repeating and self-feeding cycles of reactions, the only argument for extra-solar is the added timescale and potential additional area for productive area for pre-life to evolve in.

    Given that the universe is 13.7 billion years old, and the earth is 4.5 billion years old, and life on the earth is nearly that old, and that the universe has only been cool enough to support planets or life for much of that time, I don't believe panspermia buys us that many more orders of magnitude of time to work with.

    So, it doesn't buy us time, how about area? Again, I can only guess using very rough psuedo-numbers here, but the matter we could get from previously existing worlds or small super-fertile comets has to come from somewhere previous. Given the expanding nature of the universe, we're generally only going to be getting a pie-slice of potential sources for any life-by-projectile, and each of these sources has to have been fed by enough nuclear sources to make the building blocks of simple pre-life. I can imagine a multiplication of potential sources this way, and even though it would only take one source to seed the whole set... just imagining the mass that actually makes it into out solar system, and then actually hits our earth... that likelihood doesn't seem much stronger than the numbers we think of with abiogenesis via selective pressures here on earth.

    Ryan Fenton
  • by wisebabo (638845) on Tuesday August 14, 2007 @02:52PM (#20228167) Journal
    I can't believe that they really can begin to propose odds like that on life's origin. What if life didn't begin with clays acting as catalysts for chemical reactions but instead required a reducing atmosphere? (Current thinking is that life originally used hydrogen sulfide as an energy source, possibly from undersea "smokers"). Can the comets provide that kind of environment? What would happen when the few nascent life forms that survive the planetary bombardment that they are part of are dumped from their interplanetary cocoons into the tremendously different environment of the early earth? Don't you think that there is a good idea that the life forms that survived that environment were the ones that evolved there?

    Add to that the fact that we really don't have a clue as to how life started here (or anywhere else for that matter) and you really begin to question the judgment of giving odds to this sort of thing.

    I'm not saying they're wrong, I like panspermia theories as well. It's just for people to put some sort of numerical values on this kind of thing when we know so little is just well crazy. And what numerical values! Maybe after if we send out some cometary probes and find them teeming with primitive life could you claim such a thing. Even then do they use DNA or RNA? Any evidence of spectral emission lines of this from any of our flyby probes? (It would be even more earth-shaking if there was DIFFERENT life there!)

    Still I enjoy reading ScienceDaily.com. (Daily in fact) It's a great site not like some pseudo New-Scien(tist) kind of site.
  • Not even wrong... (Score:4, Insightful)

    by LauraLolly (229637) on Tuesday August 14, 2007 @03:08PM (#20228437)
    This looks like an exercise in finding data and pulling out numbers to support conclusions that were already reached. If you look at the pattern of papers by NC Wickramasinghe, since the 1980's he's been publishing stuff [google.com] that appears to be conclusion-oriented, rather than data-oriented, all with the conclusion that fully-formed life rained down upon the earth, embedded in comets.

    There's no doubt that comets rain down on the earth. There is considerable controversy [google.com] regarding the frequency, size, and origin of comets raining down upon the earth.

    Wickramasinghe's conclusions appear to be speculation masquerading as science. What he's proposing doesn't appear to be testable. As Wolfgang Pauli said of other proposals that were untestable, "not even wrong."

  • by sgage (109086) on Tuesday August 14, 2007 @03:18PM (#20228603)
    It's my opinion that we don't know nearly enough about abiogenesis to go making claims like this. We simply don't know how life/replicators/whatever originated to go assigning goofy probabilities. But it makes for a snappy headline.

    Whatever.

  • Bad math? (Score:3, Informative)

    by SirBruce (679714) on Tuesday August 14, 2007 @03:58PM (#20229127) Homepage

    They also point out that the billions of comets in our solar system and across the galaxy contain far more clay than the early Earth did. The researchers calculate the odds of life starting on Earth rather than inside a comet at one trillion trillion (10 to the power of 24) to one against.
    Okay, that seems like a simply calculation... given the total amount of clay all the comets, compared to the total amount of clay on Earth, and you're more likely to get like starting in a comet, if clay is factor. However, this doesn't include how much clay is on other planets, or asteroids. This method also doesn't addess the fact that life could start somewhere and then die. Of those billions of comets, very few ever actually *impact* the Earth, which is what would be required for life in one to spread here. So the real statistical comparison is the total amount of clay that has impacted the Earth from comets vs. the total amount of clay on Earth to start with, and in that case I suspect Earth wins. Life that may have started in a comet that never impacted Earth is rather irrelevant. (And we're just assuming all secondary paths, like comet -> Mars -> Earth are far less likely to consider.)

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