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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)."

14 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 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.

    4. 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!
    5. 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.
    6. 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.

  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.

  3. 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.

  4. 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.

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

    ...polluting space for aeons...

  6. 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"
  7. 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/
  8. 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.