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Chicxulub Impact Might Have Spread Life-Bearing Rocks Through the Solar System

Posted by samzenpus on from the big-boom dept.

KentuckyFC writes "Some 65 million years ago, an asteroid the size of a small city hit the Yucatan Peninsula in what is now Mexico, devastating Earth and triggering the sequence of events that wiped out the dinosaurs. This impact ejected 70 billion kg of Earth rock into space. To carry life around the Solar System, astrobiologists say these rocks must have stayed cool, less than 100 degrees C, and must also be big, more than 3 metres in diameter to protect organisms from radiation in space. Now they have calculated that 20,000 kilograms of this Earth ejecta must have reached Europa, including at least one or two potentially life-bearing rocks. And they say similar amounts must have reached other water-rich moons such as Callisto and Titan. Their conclusion is that if we find life on the moons around Saturn and Jupiter, it could well date from the time of the dinosaurs (or indeed from other similar impacts)."

45 of 161 comments (clear)

  1. And Vise-Versa by Press2ToContinue · · Score: 4, Interesting

    A nice example of panspermia.

    --
    Sent from my ENIAC
    1. Re:And Vise-Versa by MightyMartian · · Score: 4, Insightful

      A nice example of how panspermia might happen. It's a helluva leap between having life-bearing rocks blasted off of earth by a massive meteor collision, and quite another to suggest that the rest of the solar system could have been seeded.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    2. Re:And Vise-Versa by SJHillman · · Score: 5, Funny

      There are those who believe...that life out there began here, far across the Solar System...with tribes of dinosaurs...who may have been the forefathers of the Europans...or the Callistians...or the Titans...

      Some believe that there may yet be descendants of microbes...who even now fight to survive—somewhere beyond the heavens!

    3. Re:And Vise-Versa by ShanghaiBill · · Score: 3, Informative

      Liquid water? Check!

      Maybe not. Europa is believed to have an ice layer between 10 and 30 km thick. It is unlikely that an impact by a 3m rock would penetrate more than 100m or so. The impact would melt some water, but it would quickly refreeze. Europa's surface is pocked with craters millions of years old, so there does not appear to be a regular turnover of the ice that would carry any surviving life to the ocean below.

    4. Re:And Vise-Versa by hubie · · Score: 2

      From the first paragraph in their paper:

      Panspermia is the hypothesis that life can be spread between planets and planetary systems. One class of panspermia is lithopanspermia, in which pieces of rock are the mechanism for dispersal (Tobias & Todd, 1974; Melosh, 1988). Rock fragments can be ejected from an inhabited planet's surface via large meteor impact. This ejected material can then travel through space and may land on another planet or moon, as we have seen in identified meteorites from Mars found on Earth (Bogard & Johnson, 1983; Carr et al., 1985). If an ejected rock encases sufficiently resilient organisms, life could be seeded on its destination planet or moon.

    5. Re:And Vise-Versa by Charliemopps · · Score: 4, Insightful

      Europa has liquid water geysers, and fissures that routinely open up and then re-freeze. Think of the top layer of ice as our earths crust and the (possible) liquid ocean beneath like our liquid rock core. The surface ice shifts constantly and allows briney water to escape to the surface before it re-freezes.

      Now, what are the chances that a microbe laden rock would land in one of these crevasses? Pretty low, but keep in mind it's frozen, and could remain frozen on the surface for a very long time waiting for a crack to open beneath it. The odds are still pretty low I admit, but then keep in mind that these large collisions, microbe laden asteroids and Europa's ice flows have been going on for billions of years. Even if the odds per event are almost nil, the cumulative effect is staggering.

      When I think of space, I find it hard to believe anything is "impossible" given the vastness and near timelessness of it all. Granted there are some universal physical laws (speed of light) that make some things impossible. But anything that is simply "very very unlikely" has probably already happened.

    6. Re:And Vise-Versa by hubie · · Score: 3, Insightful

      This is addressed in the paper. The paper abstract:

      Material from the surface of a planet can be ejected into space by a large impact, and could carry primitive life forms with it. We performed n-body simulations of such ejecta to determine where in the Solar System rock from Earth and Mars may end up. We find that, in addition to frequent transfer of material among the terrestrial planets, transfer of material from Earth and Mars to the moons of Jupiter and Saturn is also possible, but rare. We expect that such transfer is most likely during the Late Heavy Bombardment or during the next one or two billion years. At this time, the icy moons were warmer and likely had little or no icy shell to prevent meteorites from reaching their liquid interiors. We also note significant rates of re-impact in the first million years after ejection. This could re-seed life on a planet after partial or complete sterilization by a large impact, which would aid the survival of early life during the Late Heavy Bombardment.

    7. Re:And Vise-Versa by Derek+Pomery · · Score: 2

      Hm...

      Well, from the actual research paper...
      "They estimate that a rock of 3 m across shields D. radiodurans for 10 Myr, and 3.3 Myr for B. subtilis"

      10 million years is a loooong time. The simulations were calculating in the mere kiloyears according to the paper.

      Take oneof the higher ejection velocities... 12.41km/s - let's make it a nice round 10km/s.
      Aaaaand, pick a solar system near-ish to us, that is known, like 10.5 light years away. Call it 10^14 km away...

      That's a mere third of a million year transit time. So, like a mere 3% of the survival time for Radiodurans w/ a direct trajectory. And ofc, it doesn't necessarily have to survive fully capable to replicate. Even a bunch of starter DNA would be a big help to the new planet.

      --
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    8. Re:And Vise-Versa by Samantha+Wright · · Score: 4, Informative

      It's pretty problematic that the impact in question happened in Mexico. The Yucatan isn't exactly a haven of extremophiles—you wouldn't expect to find anything that can maintain a biosphere without a good light source, and they're definitely not well-adapted to the sulphur and magnesium contamination that Europa appears to have. Unfortunately the best places to find organisms with a chance of surviving in this kind of environment are at the bottom of the ocean, which is a particularly bad target for producing ejecta. Caves are also a possibility, and since Mexico has no shortage of them, they might be a potential avenue... but who knows if there were any decent ones in the Yucatan at the time.

      --
      Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!
    9. Re:And Vise-Versa by symbolset · · Score: 4, Insightful

      Not really. Somebody computed the likelihood of Chicxulub material making its way to the nearest stars and found it not only a certainty, but they were able to estimate the total mass per neighboring star, the time en-route, and so on. In the roughly 3.5 billion years since life arose on Earth the sun has made 17 laps around the Milky Way. The Oort cloud is fairly well polluted with life. Sometimes a star comes a little too close, and we do some border trade on the frontier. Interstellar comets pass through every year gathering up a little bit on their lonely journey. Sometimes they run into things, and leave a little litter from what they've picked up on their road trip. Consider that the Milky Way had an 8 billion year head start on us, and the conclusion is obvious.

      Space is big. Really, really mind-bogglingly big. But time is also long.

      --
      Help stamp out iliturcy.
    10. Re:And Vise-Versa by TapeCutter · · Score: 3, Interesting

      There are those who believe...

      *The emperor rises to his full height slapping his testicles together in applause*

      Bravo Court Jester, another wonderfully funny and politically astute show. Your best show yet - if I may be so bold as to critique your art.

      *For the first time during the evening, the audience is silent, you can hear the tension in the air but nobody dares so much as a whisper*

      Let it be known to my court, there are some in the empire who take their sci-fi too literally and talk of the solar system as a real place where Europeans - or whatever they're called - exist.
      We must all take care not to confuse reality and fantasy in our daily conversations because such talk without the sharp comedic wit of a professional artist is a threat to our very survival. As we know it promotes the heinous crime of irrational thinking when it's is plain for all to see that there is nothing beyond the celestial ice dome but more celestial ice dome. What is it about "ice all the way up" that is so hard for some in my court to comprehend? Well I believe Octopus' razor tells the court that nobody is that reallystupid, the best mathematicians of the court are all convinced the stories are a sophisticated code for subversive activities of the court's enemies. They must be stopped or they will rip the court asunder!

      *Set to sinister music* - The emperor slowly withdraws back into his emerald green exoskeleton until only his four eyestalks are visible to the audience, all the while taking mental notes on those who are not enthusiastically applauding his own politically pointed performance.

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    11. Re:And Vise-Versa by ShanghaiBill · · Score: 4, Informative

      The Yucatan isn't exactly a haven of extremophiles

      There are extremophiles everywhere if you go deep enough. Endoliths (organisms that live inside rocks) have been found at depths of 3 km, and probably commonly live even deeper. Endoliths can endure temperatures of 120C (250F), and have also been found in the extreme cold and low humidity of the Dry Valleys of Antarctica. If anything can survive the journey to Europa, it is probably an Endolith.

    12. Re:And Vise-Versa by philip.paradis · · Score: 2

      Oh my, that was supposed to be a link to a Philosoraptor pic, but it appears I had to wrong URL in my buffer. Sorry about that, folks!

      --
      Write failed: Broken pipe
    13. Re:And Vise-Versa by VortexCortex · · Score: 2

      The Yucatan isn't exactly a haven of extremophiles

      Whom were ancestors of the extremophiles? Only other extremophiles, or have they sprang forth from more nominal relatives? When I consider that getting trapped under a glacier has caused live to live with little or no oxygen (blood falls), I often wonder just how hard it is to become an extremeophile? Perhaps the extremophiles really aren't so extreme after all? Perhaps every environment can be seen as extreme depending on your point of view.

      I mean, here on earth we have life using a sulfate catalyst to respirate via ferric ions -- A metabolism never before seen anywhere else. One season the ice forms above a pool of water, and just never recedes -- Surely, one would assume certain death of all life therein... and be very wrong, indeed. I can't bring myself to form strong opinions of the conditions under which life can not survive...

      Unfortunately the best places to find organisms with a chance of surviving in this kind of environment are at the bottom of the ocean

      Interestingly, we used to think that NOTHING could survive at those depths, yet they are teeming with life. This is a "problematic" situation, indeed. Forgive me, if I'm skeptical of pessimism: My arrogance and chauvinism has been worn down over the years by nature proving my brain not special, and its thinking wrong time and time again.

  2. If we find it, the obvious tests by JoshuaZ · · Score: 4, Informative

    At this point, we have a pretty good understanding of using genetics to estimate roughly when two populations diverged. If we find such life, we can first test if it at all resembles Earth life. If it does (in the sense that it uses most of the same amino acids, and uses similar machinery for DNA and replicating DNA), then we should be able to get a rough estimate of when it separated from Earth life based on how genetically different it is. There will be some difficulty with this sort of technique, since the life on alien worlds may be subject to extreme selection pressures, but that should be something we can roughly account for.

    1. Re:If we find it, the obvious tests by i+kan+reed · · Score: 3, Insightful

      Well, yes and no. The genetic drift measurements we use depend on a relatively consistent rate of selection. A few generations in a hyper-extreme environment, with lots of territory and niches to gain, and lots of extinction potential might happen at a substantially faster and less predictable rate. Especially since extreme environments have been shown to affect mutation rate.

  3. Would not survive by Anonymous Coward · · Score: 3, Funny

    Dinosaurs were adapted very well of a N2 / O2 atmosphere and would not survive very well in the atmospheric mix of Europa or Titan, even if they did survive the journey there in their adult or larval stages. Aside from that, they need a very specific diet to survive that would not exist on any of the moons or planets they might find themselves on after re-entry. To the best of our knowledge, photosynthesis occurs on only a single body in the Solar System - Earth. We would be able to spot it's telltale signs if it occurred elsewhere.

    1. Re:Would not survive by ganjadude · · Score: 2

      I am pretty sure that the article was not referring to the rock being blasted out there with little baby dinosaurs hitching a ride, more like virii and bacterium, and other single celled organisms. but in typical /. fashion I did not RTFA so maybe im wrong and maybe they are talking about t rex and stegosaurus chillin on the moons of Jupiter

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      have you seen my sig? there are many others like it but none that are the same
    2. Re:Would not survive by SJHillman · · Score: 3, Interesting

      Fun fact: Evidence suggests that life was around on Earth for some 200 million years before photosynthesis; Even after the evolution of photosynthesis, it would have likely taken millions more years for it to change the atmosphere in any way detectable to visitors... nevermind distant observers. Although its presence may be a telltale sign of life, the absence of it shouldn't be taken as evidence of no life.

    3. Re:Would not survive by ColdWetDog · · Score: 3, Funny

      But I like the idea of a 'larval' T. Rex falling down on some foreign planet or moon and reproducing. Jurassic Park in Space?

      No, no Mr. Spielberg, that was a joke. Please don't do that. Don't write that down.

      --
      Faster! Faster! Faster would be better!
    4. Re:Would not survive by michelcolman · · Score: 2

      Well, science has shown that dino DNA in amber has degraded so much that it would be impossible to create a real Jurassic Park with it. However, DNA on a rock that flew into space and stayed at very low temperatures might give better results, right? So they could come up with a scenario in which a space ship flies to Titan, finds a rock containing dino DNA, incubates it into a real life T-rex on board the ship, etcetera. It will be unlike any movie ever done before!

  4. Chigs! by wang620 · · Score: 2

    Watch out for Chiggie von Richthofen...

    1. Re:Chigs! by mmell · · Score: 2

      The shows protagonists were a group of young, untried Marines earning their hash-marks during an unexpected (and punishing) war. Several dark and highly controversial issues and themes were explored during the show's brief run. Yes, it's dark, grimy, sad - if you were expecting comedy and lighthearted entertainment, perhaps you should stick with "Friends".

  5. Re:incorrect! by Anonymous Coward · · Score: 4, Funny

    jesus was the one who liberated the dinosaurs - i have seen pictures of him riding one!

    What ignorance. The dinosaurs were killed during the global flood. They couldn't fit in Noah's Ark.

  6. seems extremely unlikely by epyT-R · · Score: 5, Interesting

    At the point of impact, aren't we're talking millions of degrees of heat energy? Wouldn't this sterilize anything ejected from the planet?. This whole premise sounds more like a bad scifi movie than a real hypothesis.

    1. Re:seems extremely unlikely by MozeeToby · · Score: 3

      Rock is a pretty good insulator and the impact would have thrown boulders from well away from ground zero. Basically, you've got a single shot Orion Drive with rock instead of a steal shield. You'd actually have a harder time keeping a rock cool on the way up and out than from heat directly from the blast; you'd have to leave the ground significantly above escape velocity to maintain that speed through a few dozen kilometers of atmosphere.

    2. Re:seems extremely unlikely by Runaway1956 · · Score: 2

      Just for the sake of argument - an impact that size, ejecting one or more huge fragments of the earth's crust, would necessarily rip the atmosphere apart pretty thoroughly as well. Smaller fragments of the earth's crust might follow behind a large fragment, travelling in a near vacuum. We could probably model some of those rocks escaping the atmosphere without being heated enough to be sterilized. I put this in the realm of possibility, but I don't put it high in the realm of probability.

      --
      "Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
    3. Re:seems extremely unlikely by painandgreed · · Score: 2

      Rocks burn up falling through atmosphere. Were talking about accelerating a rock upwards from the ground through the same air into space.

      Rocks burn up in the atmosphere because of the large delta-v between them and the earth. Something falling straight down as if dropped would not have this issue any more than the guy that jumped from space. Escape velocity for the Earth is 11 kms and 42 for the solar system. Unsure what that would look like but given the case, the sample in question would not be shot like out of a gun through atmosphere but likely pushed out by a pressure wave along with everything including the atmosphere around it at the same time. It would be subject to some serious Gs and perhaps compression, but friction with things around it probably wouldn't be an issue as everything in the vicinity would be traveling in the same direction at the same speed.

  7. Cthulhu did it. I was there. by madmarcel · · Score: 2

    For some reason I read that as:
    "Cthulhu Might Have Spread Life Through the Solar System"

    to which the answer is: Probably not.

  8. Earthlings... by Jedi+Holocron · · Score: 4, Funny

    ...polluting space for aeons...

    1. Re:Earthlings... by symbolset · · Score: 2

      Life is absurdly contagious.

      --
      Help stamp out iliturcy.
    2. Re:Earthlings... by Lightning+McQueen · · Score: 2

      This! There's so much junk in space it's like you don't have to worry if your ship breaks down. Find an old 1960's version of your broken part floating around (probably be within 10 feet of you) pop it in and your good to go.

  9. Re:incorrect! by TheCarp · · Score: 4, Insightful

    Nuh uh. Animals don't have souls[1]

    [1] Ref 1989 - Confraternity of Christian Doctrine class - incidentally the very topic that convinced me finally that "they just made all this up", and convinced me, much to my mother's dismay, that I was done with CCD and religion.

    --
    "I opened my eyes, and everything went dark again"
  10. Attempt No Landing There by tverbeek · · Score: 4, Funny

    The Sentinel is going to be pissed that we'd already contaminated Europa.

    --
    http://alternatives.rzero.com/
  11. Re: incorrect! by ColdWetDog · · Score: 3, Funny

    "isles and isles of documentation"

    So you are saying that somewhere, in some distant and unexplored ocean there are islands filed with mouldering ancient texts that explain the origin of life, the universe and everything? Fascinating.

    Have you considered pitching this idea to a video game company?

    --
    Faster! Faster! Faster would be better!
  12. Re: incorrect! by Runaway1956 · · Score: 3, Interesting

    Good question. One which few people will even touch. Fact is - there is no such restriction. If a God or gods meddled in life here, they had all the same reasons to plant life hundreds, thousands, millions, or quintillions more times around the universe. One of the crazier stories I read in my youth had God and Satan taking turns designing newer and better planets. On this planet, God is the creator, on the next planet, Lucifer is the creator and God is the antagonist.

    --
    "Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
  13. Re:Amazingly Earth-centric viewpoint... by hubie · · Score: 2

    Imagining that all life must have originated from Earth is an amazingly earth-centric point of view

    This claim is not made anywhere in the paper, or anywhere else for that matter that I can find.

  14. Re: incorrect! by icebike · · Score: 3, Insightful

    I'm sure the point was not missed.

    But I'm also sure the misspelling grabbed ColdWetDog's eyeballs and bitchslapped them so hard that was necessary to triple read the post just to extract any meaning, while at the same time choking back a guffaw.

    --
    Sig Battery depleted. Reverting to safe mode.
  15. I think you've missed something . . . by mmell · · Score: 4, Insightful
    Yon organic matter needn't survive, reproduce and grow - it only needs to introduce the kind of complex organic molecules (amino acids, protiens, etc.) which form the foundation of evolutionary life on this planet. Hell, all the microbes in question (be there one or one million) can die on impact as long as their protiens/nucleic acids etc. remain (even partially) intact. Planetery physics will take care of the rest.

    Just don't expect anything familiar to evolve out there.

    1. Re:I think you've missed something . . . by Sique · · Score: 2

      If it is much colder (as on Europa or Titan), then the van't Hoff rule just lets us expect the evolution being much slower (about 2-3 times per 10 degrees).

      --
      .sig: Sique *sigh*
    2. Re:I think you've missed something . . . by Kongming · · Score: 2

      While I will agree that 65 million years is not long in geological time, any novel life forms trying to develop on Earth have to compete for limited resources with existing organisms that are already well-adapted to their environments. It is probably much less likely for some alternative to cellular life as we know it to develop here in parallel with existing life than it is somewhere that we seed a supply of proteins and amino acids and watch to see what happens.

      --
      (no sig)
  16. Table 5 by ZombieBraintrust · · Score: 3, Informative

    The 20,000kg number is from Table 5 in the journal. I think the summary is a little deceptive.
    Probablilty of life bearing rock ejected from earth reaches Europa is: 2.8E-6 ± 5.0E-7 %
    Yeah thats .0000028% plus or minus .0000005%
    Including all rocks that were ejected they believe 6 plus or minus .9 rocks would reach Europa.
    The 20,000 Kg number comes from those 5 to 7 rocks.

  17. Re:There's no Vise, and no Versa either! by Deadstick · · Score: 2

    Earth is still throwing rocks into space in modern times, a significant portion of what was once the island of Krakatoa is now in space.

    Cite? Throwing rocks into space is one thing; throwing them so they don't come back is quite another. Absent an injection thruster that kicks in at the right height, the only way to prevent an object coming back down is to accelerate it to escape velocity. That's a tall order.

  18. Re:Amazingly Earth-centric viewpoint... by Hatta · · Score: 2

    leaving far too little time for life to form in primordial Earth oceans under any sort of process currently envisioned.

    While any of the individual chemical reactions required for abiogenesis would be exceedingly rare, you have to consider that they were taking place in parallel across the surface of the Earth. The Miller-Uray experiment ran for a week in a few small flasks. You can expect much less frequent reactions to happen, at least once, when you do the same thing in the entire volume of the oceans over the course of 100 million years.

    --
    Give me Classic Slashdot or give me death!
  19. Re:incorrect! by Zordak · · Score: 2

    It's really more of an inverse "no true Scotsman." There are plenty of people who claim "No true Christian believes X, because Christianity is defined [by me] as people who believe Y." But the GP's thesis was that "Different flavors of Christianity believe everything from A to Z." If you define "Christianity" broadly as "people who believe in the New Testament," you will find a great deal of variance.

    --

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