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Earth Space Science

Meteorites Brought Ingredients of Life To Earth 199

Posted by Roblimo
from the we-have-met-the-aliens-and-they-are-us dept.
Meshach writes "A new analysis of a meteorite found in Antarctica is leading scientists to think that life on Earth may have come from outer space. Chemical analysis of the meteorite shows it to be rich in ammonia and containing the element nitrogen. Nitrogen is found in the proteins and DNA that form the basis of life as we know it. The prevailing theory is that our planet may have been seeded by a comet or asteroid because the formative Earth might not have been able to provide the full inventory of simple molecules needed for the processes which led to primitive life."
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Meteorites Brought Ingredients of Life To Earth

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  • by gandhi_2 (1108023) on Monday February 28, 2011 @10:51PM (#35344186) Homepage

    ..the meteorites were intelligently designed!

    Boom.

    • by dudpixel (1429789)

      "What specifically caused life to begin on Earth remains a mystery. Professor Pizzarello hypothesises material from a meteor may have interacted with environments on Earth such as volcanoes or tidal pools, but says all remains a matter of guess work."

      We should totally base our worldview around this.

      • Re:Yes, but.... (Score:5, Informative)

        by ColdWetDog (752185) on Monday February 28, 2011 @11:17PM (#35344356) Homepage
        Well, lets try to up the quality of the discussion and at least provide the abstract [pnas.org]:

        Abundant ammonia in primitive asteroids and the case for a possible exobiology

        1. Sandra Pizzarelloa,1, 2. Lynda B. Williamsb, 3. Jennifer Lehmanc, 4. Gregory P. Hollanda, and 5. Jeffery L. Yargera

        Abstract

        Carbonaceous chondrites are asteroidal meteorites that contain abundant organic materials. Given that meteorites and comets have reached the Earth since it formed, it has been proposed that the exogenous influx from these bodies provided the organic inventories necessary for the emergence of life. The carbonaceous meteorites of the Renazzo-type family (CR) have recently revealed a composition that is particularly enriched in small soluble organic molecules, such as the amino acids glycine and alanine, which could support this possibility. We have now analyzed the insoluble and the largest organic component of the CR2 Grave Nunataks (GRA) 95229 meteorite and found it to be of more primitive composition than in other meteorites and to release abundant free ammonia upon hydrothermal treatment. The findings appear to trace CR2 meteorites’ origin to cosmochemical regimes where ammonia was pervasive, and we speculate that their delivery to the early Earth could have fostered prebiotic molecular evolution.

        Without the full article it's hard to really follow why they think the earth needed excess organic chemicals, even specific amino acids, to be provided from meteorites. There is a large body of data that shows that amino acids, nucleic acids, lipids and a host of other moderately complex organic molecules could have been formed on earth at various times in it's development. As far as I can tell, there is nothing magical about the meteorite derived molecules and hence invoking panspermia (or more accurately, panorganicmoleculermia) is really unnecessary.

        Anyone else out there with either access to PNAS or some better insight? So far it's a big meh.

        • Re:Yes, but.... (Score:4, Interesting)

          by Afforess (1310263) <afforess@gmail.com> on Tuesday March 01, 2011 @12:04AM (#35344654) Journal
          I'm not an expert - so I may be wrong here.

          As I understand it, life evolved QUICKLY on Earth. I mean, we went from a barren rock with magma flows and some water to teeming lakes of bacterium in the blink of an eye. (Relatively speaking). Only 500 million years after the heavy bombardment from meteors, and a mere 25 million years after the moon formed, Prokaryotes and Eukaryotes formed. As far as the universe goes, that's hardly any time at all.

          The best explaniation for this rapid growth is that life didn't actually have to start here, but came from meteorites.

          Again, I am not an expert, just an interested college student. Anyone with real knowledge, please correct me.
          • Re:Yes, but.... (Score:5, Informative)

            by interactive_civilian (205158) <mamoru@gmaiTIGERl.com minus cat> on Tuesday March 01, 2011 @12:30AM (#35344778) Homepage Journal

            I'm not an expert - so I may be wrong here.

            As I understand it, life evolved QUICKLY on Earth. I mean, we went from a barren rock with magma flows and some water to teeming lakes of bacterium in the blink of an eye. (Relatively speaking). Only 500 million years after the heavy bombardment from meteors, and a mere 25 million years after the moon formed, Prokaryotes and Eukaryotes formed. As far as the universe goes, that's hardly any time at all.

              The best explaniation for this rapid growth is that life didn't actually have to start here, but came from meteorites.

              Again, I am not an expert, just an interested college student. Anyone with real knowledge, please correct me.

            Your numbers seem off...

            It was about 200-400 million years from the end of major bombardment to the first geological evidence of life on Earth. The moon formed before major bombardment ended. Approximate dates are 4.6Gya for Earth, 4.5Gya for the moon, 4.2Gya for the end of late heavy bombardment, and 3.8Gya for the first fossil evidence of life). The Wikipedia article on geologic time [wikipedia.org] gives a pretty good overview. :)

            As for the GPP, I agree. Every time they find something like this, there's always the "So Earth was seeded by these" speculation. It seems that such materials are rather common in our solar system, both here on Earth, on other planets, and on meteors and asteroids. If such organic molecules can form with relative ease in so many other places in the solar system, I see no reason why they couldn't have formed on Earth as well as it went through it's own geological evolution. Especially when geological processes for forming many complex organic chemicals abiotically have been documented. No doubt that stuff falling from the sky could contribute to organic materials on Earth, but I see no reason to believe that they are a major contribution.

            As for TFS, I found this to be rather humorous:

            Chemical analysis of the meteorite shows it to be rich in ammonia and containing the element nitrogen.

            Well, I should hope so. I'd be very surprised and impressed if the meteorite were rich in ammonia but didn't contain nitrogen. :p

            • by Woek (161635)

              Thank you for that comment; this is exactly what I came here to post. It's nice to see other people having the same opinion... I mean 'common sense'.

            • by Urkki (668283)

              As for the GPP, I agree. Every time they find something like this, there's always the "So Earth was seeded by these" speculation. It seems that such materials are rather common in our solar system, both here on Earth, on other planets, and on meteors and asteroids. If such organic molecules can form with relative ease in so many other places in the solar system, I see no reason why they couldn't have formed on Earth as well as it went through it's own geological evolution. Especially when geological processes for forming many complex organic chemicals abiotically have been documented. No doubt that stuff falling from the sky could contribute to organic materials on Earth, but I see no reason to believe that they are a major contribution.

              Well, different molecules require different environments to form, and I think it's a least likely, that some necessary molecules could only be formed outside Earth. If they didn't rain on Earth with meteorites, there might not have been life, because critical building blocks would have been missing.

              Speculation in my part of course,and in any case it's hard to know which molecules these were, and certainly nothing "astromystical" about it.

            • by Ihmhi (1206036)

              Here's some stream-of-consciousness, ad-libbed sci-fi for you.

              December 11, 2012: A meteorite containing ammonia and sodium percarbonate slams into Alabama, dissipating mustard gas into the air.

              December 12, 2012: Local civilization rapidly falls apart. The federal and state governments promise relief.

              December 13, 2012: The International Red Cross, Salvation Army, and local volunteers spring to action. Mass looting, rioting, and general disarray are seen. Citizens organize into militias to defend their nei

          • by Dahamma (304068)

            In my undergrad biology lab, we replicated the Miller-Urey experiment that created some amino acids from water and a few gases in a sealed system with a spark gap in a few days.

            http://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment [wikipedia.org]

            The earliest known fossil evidence of prokaryotic life is almost 1 billion years after the Earth's formation. I can't imagine how you can call 1 billion years any time at all, even in the scale of the universe :)

            But if you are curious about the history and research on the to

            • The earliest known fossil evidence of prokaryotic life is almost 1 billion years after the Earth's formation. I can't imagine how you can call 1 billion years any time at all, even in the scale of the universe :)

              It's easy. I call it on the order of 10% of the current age of the Universe.

              • by Dahamma (304068)

                Uh, that should be "how you can call 1 billion years NOT any time at all". Though I'd hope from the actual context of my post you'd get that I was saying and you're just being nitpicky.

                But if you think 1 billion years is not significant in astrophysical as well as evolutionary scales, I can't help ya...

          • by C0R1D4N (970153)
            What is your basis of comparison? Without observing the process occur elsewhere for all we know life evolved very slowly on earth.
          • I'm not an expert - so I may be wrong here.

            Ten minutes is all it takes to understand the leading theory of aboigenisis. No ridiculous probabilities, no supernatural forces, no lightning striking a mud puddle. Just chemistry! [youtube.com] Nitrogen and ammonia were both abundant in the "second atmosphere" (archean era) [eiu.edu] which is when the oceans and life first formed.

          • by wcrowe (94389)

            The best explaniation for this rapid growth is that life didn't actually have to start here, but came from meteorites.

            Are you sure this is what you meant to say? If you're saying the ingredients for life came from meteorites (as the article states) then okay. But, if you're saying that fully-formed life itself came from meteorites, then it begs the question, "where did that life originate?

            Just asking for clarification.

      • "What specifically caused life to begin on Earth remains a mystery. Professor Pizzarello hypothesises material from a meteor may have interacted with environments on Earth such as volcanoes or tidal pools, but says all remains a matter of guess work."

        We should totally base our worldview around this.

        +1

  • Panspermia (Score:2, Insightful)

    by JWSmythe (446288)

        Welcome to the Theory of Panspermia.

        And why did they have to call it something that sounded so perverse?

    • by shawb (16347)
      This is far from panspermia. That is the theory that life itself came from space. This is just saying that Nitrogen is brought to the earth by meteorites.

      Really, this should just be one big "duh" to anyone who has read up on theory of planetary formation. Basically, the whole planet is made up of meteorites that crashed together. And maybe a couple times it was large aggregations of meteorites that collided into the growing mass, and even small planetoid bodies such as the event that is theorized to
      • by JWSmythe (446288)

        I'll kind of give you that one. We're really splitting hairs though. All of the pieces, or a complete basic organism, which one wins.

        I will agree totally on the planetary formation though. Planets are large lumps in space that grew through contributions of generally disorganized matter colliding. If it ends up being a sufficient side, in an orbit, and rotating, it's probably a planet. If it doesn't achieve an orbit it'll likely become a contribution to the next closest body

  • They had to come from somewhere right?

    • Re:Makes sense (Score:4, Insightful)

      by Palmsie (1550787) on Monday February 28, 2011 @11:02PM (#35344256)

      Not quite, complex organic compounds are found throughout our solar system. For example, on Titan it literally rains organic compounds that, when mixed with water, form amino acids. It is a plausible hypothesis that a third party could have brought such compounds to earth but it is also equally likely that earth simply formed them on its own. If Earth could have formed them on its own it doesn't require the third party hypothesis.

      • by RichiH (749257)

        > equally likely that earth simply formed them on its own

        I don't claim to understand the exact science behind it, but apparently this is not as likely. And, also apparently, it happened too fast for many people's liking.

        I am not saying it's that way, mind. Just that, from what I know, external seeding solves the problem in a nicer way.

  • TFS says that the meteorite is "rich in ammonia and contains the element nitrogen." Considering that the chemical formula for ammonia is NH3, it's hard to see how it could possibly not contain nitrogen.
  • Article says the theory is that metorites brought it required ingredients to Earth.

    Summary says might.

    Title says did.

    In reality, everything on Earth came from space according to current scientific theory, the planet coleased into existence from matter orbiting Sol a few billion years ago.

    So, I'm not really sure why you would consider this news, the 'ingredients for life' were more than likely ALREADY HERE by the time the Earth qualified as a planet, and most certainly by the time it cooled enough to not des

    • by fishexe (168879)

      Article says the theory is that metorites brought it required ingredients to Earth.

      Summary says might.

      Title says did.

      Shush, you with your accurate distinctions!

    • Re:Might != Did (Score:4, Insightful)

      by tragedy (27079) on Monday February 28, 2011 @11:28PM (#35344474)

      To be fair to modern observational evidence versus historical record, historical record often isn't really all that good. Even big, fairly educated civilizations like the Romans didn't leave behind particularly reliable history. Take Caligula, for example, we know a few things about him, but many of the things we think we know are probably just made up. Historians throughout the ages have also often been popular fictional writers and little effort seems to have been put into distinguishing between their fictional works and their factual ones at the time (of course, they were writing for a contemporary audience who probably knew through context). Not to mention all of the propaganda.

      On the observational evidence end, dating by geologic layers isn't perfect, but it's still pretty good at telling us that A happened before B, which happened before C. Sure, the dates we ascribe to the events aren't perfect, but, unlike recorded history, we usually have a pretty good idea of what actually happened. We can see flood, fire, meteorite impact, earthquake, continental drift, this species vanishing, this one arising, 1000s of different species all over the globe vanishing at once, etc., etc. Even geological evidence isn't perfect and it apparently can even lie sometimes, but nowhere near as much as a human writer who may well be on drugs, just plain insane, repeating common misconceptions and rumors as fact, or just plain lying like crazy to support an agenda.

      • by Tim C (15259)

        Not to mention all of the propaganda.

        "History is written by the winner".

    • "Fifteen hundred years ago everybody knew the Earth was the center of the universe. Five hundred years ago, everybody knew the Earth was flat, and fifteen minutes ago, you knew that humans were alone on this planet. Imagine what you'll know tomorrow." - Agent K, Men In Black

    • In science, a theory is not a really good guess or a conjecture. That is a hypothesis. When something is called a theory in science, it means "We are pretty darn close to being absolutely positive that we have the majority of it right, but there are a still a few kinks we still need to work out." The fact that you think a theory is just a guess means you don't understand how science works at all.
    • by Draek (916851)

      Calling it anything other than a theory means you don't understand how science works at all.

      Ohhh, the irony [wikipedia.org].

      Anyways, the big, practical problem with your postulate is that it applies to stuff 10 million years ago just as well as whatever happened 10 seconds ago, making whatever meaning you held of "knowledge" pretty f'in useless.

  • It possessed Dr. Fred!!
  • Didn't the entire Earth come from meteorites and other space junk?
    • by dimeglio (456244)

      Pretty much. As such we're creatures of the entire universe and not just of this earth. Just so happen that things worked out better for our model on this planet.

      • As such we're creatures of the entire universe and not just of this earth.

        Thanks. Now I've got stuff like "We are stardust, we are golden, we are interstellar carbon" in my head.

  • OK, it took a few hundred million years, but it did cover the planet.

  • That's a fertilizer bomb! Thanks a lot, outer space.

  • by thepainguy (1436453) <thepainguy@gmail.com> on Monday February 28, 2011 @11:19PM (#35344380) Homepage
    Seriously, I find ideas like this to be unsatisfying because they just pass the buck. Why is it any more likely that life would arise in a comet, asteroid, or other planet than it would be for life to arise on earth? Maybe if the earth was wiped clean by some cataclysm, but I don't know of anyone who's proposed that.
    • by pclminion (145572)

      Why is it any more likely that life would arise in a comet, asteroid, or other planet than it would be for life to arise on earth?

      Why is it more likely that life arises anywhere that isn't point X, versus on point X? Well, maybe because there's trillions of places that aren't point X but only one point X. For starters.

      • Re: (Score:2, Informative)

        Wrong. The problem is, if it arises anywhere else but not in point X, now you also have to explain the extremely low likelihood of travelling from somewhere else to point X. So you have prob(not X) = prob(somewhere)*prob(go from somewhere to X), and that's even lower than prob(X).
    • by Ouka (1621177) on Tuesday March 01, 2011 @01:29AM (#35345102)

      The article didn't say life starting in space. One of the major problems with the leading hypothesis about how life began here on Earth is that many of the chemical elements required by said hypothesis were not present in sufficient quantities in early Earth. Or at least were not present based on what we think we know about the early composition of the planet. Chief among these problems is the absence of organic compounds in the rock matrix of the oldest known rocks.

      Fast forward a few hundred million years and now these ancient-but-not-oldest rocks now have organic traces. What was different from when Earth cooled vs a few hundred million years later? Uncountable millions of comet and meteor strikes. Objects that have been shown to contain just the missing ingredients needed to complete the shopping list for the formation of Life.

      Inert organic compounds have since been found throughout the known cosmos, from nebula containing ethanol to ammonia in asteroids. There are a multitude of hypothesis about why organic compounds form better in cosmic bodies instead of planets, from ionizing radiation in solar wind to the fact that planet formation is too hot an event for any traces of the compounds to remain after consolidation.

    • It's asteroids all the way down

    • I don't think anyone's saying that life arose on a comet or asteroid, only that the ingredients were deposited here by such. And I don't think anyone's saying that it didn't happen anywhere else. Indeed, rather that passing the buck, positing an extra-terrestrial origin for the required ingredients might suggest that it would be more likely (or at least possible) for the same sort of thing to happen elsewhere.
  • ...been "brought" and "could have brought".
    • They've found _one_ meteorite with the ingredient, so we know for a fact that it was 'brought' to earth... Or are you trying to claim that meteorite was planted there by some meta-physical being?
      • by fishexe (168879)

        They've found _one_ meteorite with the ingredient, so we know for a fact that it was 'brought' to earth... Or are you trying to claim that meteorite was planted there by some meta-physical being?

        I took "ingredients of life" to mean "the ingredients from which life was made", not "a bunch of stuff chemically similar to the ingredients from which life was made".

  • A few months ago I was walking with my wife/son back to our home from the library. In the seam of a manhole of an asphault jungle (I.E. downtown) ~175k population city, I saw thriving sprouts. Life will always find a way.

    If we were seeded by intelligent life, that is awesome and I can't wait to find out more. If it were completely random that in our universe, which we have no idea even the size of, meteors with just the right contents to start life in the Earth's environment came to us, then awesome as well

  • He blowed up the last chance to finally get intelligent life on earth getting rid of that meteorite.
  • by MBGMorden (803437)

    Given the whole accretion disk theory of planet formation - didn't the whole damned planet come from just a bunch of meteorites clumping together and falling to an ever larger body?

  • Not so sure (Score:5, Informative)

    by jmv (93421) on Monday February 28, 2011 @11:44PM (#35344552) Homepage

    So the Earth's atmosphere contains about 4*10^19 kg of Nitrogen (surface of the earth * 100 kPa/g * 80%). That's a *lot* of mass. A 10 km asteroid (like the one that could have wiped the dinosaurs) is maybe 10^12 kg. So it would take more than 10 *millions* of those to provide the Earth with its current atmosphere -- assuming these asteroids were pure frozen nitrogen.

    Another thing I don't quite understand is why the nitrogen would have to come from somewhere else. As far as I know, stars produce plenty of it (CNO cycle and all), so if we have carbon and Oxygen, why not nitrogen as well. Am I missing anything?

    • No, you're not missing anything at all.

      The 'meteorite idea' seems moot from the start: for a meteorite to have some importance in the 'creation of life', it has to either a) bring the elements lacking (until then) from a life-creating environment for the planet (a theory that you've disproven quite eloquently), or b) somehow be the 'instigator', between ingredients already existing on the planet, of the process that was the creation of life.

      Bioforms are a natural occurance even in space; it is their environ

  • Personally, I welcome our meteorite-borne ancestral overlords.
  • Chemical analysis of the meteorite shows it to be rich in ammonia and containing the element nitrogen.

    So meteorites brought the life-critical element Nitrogen(!) to Earth... that truly is an astounding finding... no way that life could have evolved here without that contribution from space...

    oh wait... doesn't the Earth already have "some" nitrogen? And ammonia? is that hard to make? (no don't think it is...)

  • Then scientists and creationists would at least *sound* like they agreed.

    Of course, it would make life tough for Muslim cartoonists... not being able to draw rocks anymore. But hey, even if they did and we're sentenced to stoning - as soon as someone picked up a rock to throw they could just point and yell "Forbidden Idol!!!", and nonchalantly amble away in the ensuing confusion.

  • life I thought you were going to say it brought beer.
  • Earth is in outer space. We are all from outer space. Depends on your perspective. Earth is not the center of the universe.
    • Well, if space stretches on all sides of me to infinity, that would mean that ~I~ am the centre of the universe.

  • Perhaps the great author Arthur C. Clarke was not far off in his hypothesis [astrobiology.com].

    Being descendants of... alien poo... is a humbling thought.

  • by Michael Woodhams (112247) on Tuesday March 01, 2011 @01:29AM (#35345096) Journal

    Neither the BBC article nor the abstract* of the original paper mention 'life on Earth may have come from outer space'. They say that the nitrogen may have come from outer space. From the abstract "we speculate that [ammonia rich comets] delivery to the early Earth could have fostered prebiotic molecular evolution" (emphasis mine).

    * Alas, my institution only has free access to PNAS articles older than 6 months, so I haven't seen the paper. I could probably get up and read it in the library, but reading a paper off paper just seems morally wrong. Won't somebody please think of the trees?

  • by Tablizer (95088) on Tuesday March 01, 2011 @02:28AM (#35345356) Homepage Journal

    Meteorites are like women: they bring life and love; and then smash it all to hell in a jealous fit such that you have to start all over again in another town.

  • Earth might not have been able to provide the full inventory of simple molecules needed for the processes which led to primitive life.

    Yeah because one thing the Earth is short of is Nitrogen.

  • Everything on the planet came from outer space.
  • The simplest answer is that life formed from indigenous materials on the planet. Personally I think that anywhere life is possible, life appears.

  • So I like to think of it as Space Cum. I know this sound disgusting, sorry. But if the planet is the egg and meteorite is the seed, wouldn't that basically imply that this planet and all living creatures come from some Space funk?

    Planet X meets Planet Y, they bang into each other and had a Big Bang. Their seeds now free to float in space land here and there and Wham life as we know it.... 900 million years later.

    It could happen.....

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