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Space Science

Sun's Dark Companion 'Nemesis' Not So Likely 306

Posted by kdawson
from the trilobites-look-up dept.
TravisTR passes along a story about the death of Nemesis. "The data that once suggested the Sun is orbited by a distant dark companion now raises even more questions... The periodicity [of mass extinctions] is a matter of some controversy among paleobiologists but there is a growing consensus that something of enormous destructive power happens every 26 or 27 million years. The question is what? ... another idea first put forward in the 1980s is that the Sun has a distant dark companion called Nemesis that sweeps through the Oort cloud every 27 million years or so, sending a deadly shower of comets our way. ... [Researchers] have brought together a massive set of extinction data from the last 500 million years, a period that is twice as long as anybody else has studied. And their analysis shows an excess of extinctions every 27 million years, with a confidence level of 99%. That's a clear, sharp signal over a huge length of time. At first glance, you'd think it clearly backs the idea that a distant dark object orbits the Sun every 27 million years. But ironically, the accuracy and regularity of these events is actually evidence against Nemesis' existence."
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Sun's Dark Companion 'Nemesis' Not So Likely

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  • by EmperorOfCanada (1332175) on Monday July 12, 2010 @06:43PM (#32881010)
    How long has it been since the last apocalypse? Basically is the odometer rolling around its 27 millionth year? If so can we see something coming? Dust cloud?
    • by cduffy (652) <charles+slashdot@dyfis.net> on Monday July 12, 2010 @06:46PM (#32881038)

      Read the Fine Article.

      We've got lots of time -- we're only 11 million years into this cycle.

    • 11 million years, so we have about 16 million years to figure out what happens and then do something about it.
      • by Surt (22457) on Monday July 12, 2010 @06:53PM (#32881146) Homepage Journal

        Crap, we're screwed. We are not good at planning ahead. If only we'd had more time.

        • >>>If only we'd had more time.

          Ach, why bother? In about 100 billion years all the stars will run out of fuel, and there will be nothing left but glowing embers (red dwarfs). The 'verse will be so dark you won't even be able to see, and any humans still left alive will be clinging to the embers like flies on poo, just waiting for the inevitable extinction. So why even bother to try? We're all doomed.

          "It's depressing just thinking about it." - Marvin the Robot

        • by silentcoder (1241496) on Tuesday July 13, 2010 @04:49AM (#32884814) Homepage

          Well, average life-expectancy of a species is 5-million years. Homo Sapience has already doubled that putting us at the extreme end of the scale that gives this average.
          In short, the chances of us being around long enough to need to do something is statistically negligible. Life will be around. Probably even intelligent life. Perhaps this time even life intelligent enough to do something, probably not.

          If we were wiped out tomorrow, it's quite likely that zero evidence of our existence would even be around to be found 10 million years from now. There were entire species that we know existed because we have fossils, that were around longer than us - and where we know this because we have two bones. Not two skeletons - two bones.

          The assumption that we're the first technologically intelligent species on this planet is just as unscientific as to assume we aren't. The absence of evidence in this case can be just as easily explained by deep time as that there wasn't anything to leave it. But we do have absolute proof that technological societies CAN evolve on earth - because we're here. Thus Occam's razor suggests it's more likely that it has happened before - probably several times than that it hasn't. ...sheez, and I just wanted to expand on your joke by mentioning how low the odds are of our species (or even of the entire class mamalia) still being around in 16 million years...

          • by aussie_a (778472)

            Fortunately we've left evidence external to the Earth hopefully proving forever after that there was once intelligent life on this planet. Although I'd say the likelihood of these artifacts surviving long enough is fairly negligible.

          • Re:11 million years (Score:4, Informative)

            by gentlemen_loser (817960) on Tuesday July 13, 2010 @10:08AM (#32887768) Homepage

            Well, average life-expectancy of a species is 5-million years. Homo Sapience has already doubled that putting us at the extreme end of the scale that gives this average.

            How are you doing your math? The genetic evidence shows that Homo Sapiens can be traced back 200,000 years. Nowhere near the 5 million you are stating as an average for species longevity. If you are counting Australopithecus anamensis, that would get you back to 4 million years, but I would hardly consider it to be the same species as us.

            Furthermore, the actual average longevity of a species is 1 million years, not 5 (as evidenced here [pbs.org]. Just because 10 million years appears to be an extreme upper limit does not make the average 5 million.

      • Thank God! (Score:5, Funny)

        by mangu (126918) on Monday July 12, 2010 @06:56PM (#32881188)

        11 million years

        At first I read "1.1 million years" and was really worried

      • That might be enough if we have to run the simulations in Windows.

      • by gmuslera (3436)
        We could create a commision to study the problem, that surely will create subcommission for each alternative and so on till we die in 16 millon(?) years in the black hole created by that massive weight of burocracy.

        Anyway, so far we where the first ones smart enough to build weapons capable to extinguish ourselves, while still being stupidity enough to think in using them. If we survive to ourselves the next 160 or 1600 years, we could start to think in what will come so much further.
        • >Anyway, so far we where the first ones smart enough to build weapons capable to extinguish ourselves

          And your scientific basis for this assertion is?

          We have no proof that we're the first, and frankly if we were extinguished tomorrow the statistical odds are that in 5 million years time there will be no single trace of evidence left that we were ever here. To assume that no species in the billion years or so prior to our arrival reached this level is... well it's absurd.
          Class mamalia has been around for a

          • by vlm (69642) on Tuesday July 13, 2010 @06:25AM (#32885190)

            We have no proof that we're the first, and frankly if we were extinguished tomorrow the statistical odds are that in 5 million years time there will be no single trace of evidence left that we were ever here. To assume that no species in the billion years or so prior to our arrival reached this level is... well it's absurd.

            For a geologist it would be pretty trivial to figure out. Merely analyze the distribution and size of mineral deposits of various ages. Why thats odd, all of the coal that was near the surface 5 million years ago is missing, although the stuff thats buried "too deep" 5 million years ago is still here. Same game for oil/gas, oddly enough all the large deposits that were onshore or close to shore 5M years ago are gone, how odd. Another fun one would be our trash heaps. WTF is all this indium ore near all this relatively pure glass ore? How come we find silicon deposits from 5 million years ago that are occasionally ridiculously pure except for commercially useful P-type and N-type semiconductor impurities? Finally, assuming the highly evolved cockroaches that have taken over have advanced beyond us, they'd also notice that certain technologies that they use have not been exploited, 5M years ago they were obviously pretty good at burning this "oil" stuff but they clearly never figured out how to refine boron into anti-matter reactor shielding, or mined graphite to make monocrystaline carbon fiber space elevators, much like a hundred years ago hyperpurified silicon and large lumps of pure uranium metal were not industrially produced.

            • Re: (Score:3, Insightful)

              by silentcoder (1241496)

              So you assume a previous intelligent society would have used the same fuels as us (really ? Fossil fuels used by the "people" whose time fossil fuels were LAID DOWN IN... think about that for a second).

              More than that, the very surface of the earth has been reshaped a few times. There was mass vulcanism in Siberia that covered whatever was there originally under about 2 miles of magma round about the same time as the KT event - in fact some scientists believe that the KT event could have CAUSED this... so if

      • by jamesh (87723)

        11 million years, so we have about 16 million years to figure out what happens and then do something about it.

        Yep. Just like we're tackling global warming now.

    • by Asic Eng (193332)
      How long has it been since the last apocalypse?

      From TFA: The last extinction event in this chain happened 11 million years ago.

    • As has already been suggested - read TFA. Then, read the comments. The article seems to be largely about bogus science. There isn't any real periodicity to the extinctions.

      But, even if TFA were accurate, and provable - we'll miss the next regularly schduled extinction anyway, I'm sure. We'll probably kill ourselves off first.

  • All I can think reading this is great another stupid theory that the 2012 nut jobs can latch onto.
    • by Asic Eng (193332)
      That's not really the expertise of 2012 nut jobs - you'll need some 11002012 nut jobs.
  • by Kvasio (127200) on Monday July 12, 2010 @06:45PM (#32881032)

    isn't this the most simple explaination? Most stars in Mily Way arms are known to bounce up and down the ecliptic.

    • How exactly would that work?

      The orbital period of Sol around the Galaxy seems to be almost ten times this extinction period.

      • by sunspot42 (455706) on Monday July 12, 2010 @09:15PM (#32882330)

        The sun doesn't just orbit the center of the galaxy, though. It also moves up and down relative to the galactic plane. Some have suggested that whenever the solar system reverses direction in that oscillation, very bad things happen, possibly due to the Oort Cloud experiencing some lag in reversing direction relative to the rest of the system. The sun essentially winds up off-center in the Oort Cloud, and in comparison to normal periods a lot of comets get kicked into the inner solar system as a result of this imbalance.

        • Re: (Score:3, Insightful)

          by captainpanic (1173915)

          Some movement like that (through the galactic plane) could be a reason for some instability in the Oort cloud. The galaxy is chaotic. So many objects, all influencing each other. Lots of motion around several centers of gravity and oscillations through the galactic plane too. Sure, I can see that some (galactically speaking) relatively small objects such as a 10 km rock can change orbit a little.

          We would have to prove that the instability sort of peaks every 27 million years. I hate statistics, so I am not

        • by jc42 (318812) on Tuesday July 13, 2010 @12:08PM (#32889602) Homepage Journal

          The sun doesn't just orbit the center of the galaxy, though. It also moves up and down relative to the galactic plane. Some have suggested that whenever the solar system reverses direction in that oscillation, very bad things happen, ...

          That's close to a conventional explanation, but off by 1/4 cycle. The extreme high/low points of the solar system's bobbing orbit are outside the galactic plane, and would be the low-danger points. The rough parts of the (approx. 60 million year) cycle are the two crossings through the central part of the galactic plane, which are the densest portions. During the crossings, the solar system is zipping through the galactic plane at a few hundred km/s, producing lots of collisions with whatever rubble happens to be there.

          Part of the explanation from the astronomers who've done the studies is that, although we're about in the middle of the galactic plane right now, we're actually in a "Local Bubble" about 300 light years across, so there's not much galactic rubble in the solar system right now. There are low-density bubbles like this scattered around, the results of things like supernova explosions in the distant past.

          Stick around for another million years or so, and we'll exit the local bubble. There might be some nice fireworks then, and perhaps another mass extinction.

          Of course, we are going through a mass extinction event right now, but it's an unusual one with a known causative agent that's not astronomical. It seems that a new top-level predator has recently evolved, which has been devastating the ecosystem all over the planet. This will probably confuse the paleontologists in the future, since they'll see a mass extinction during a crossing of the galactic plane, but won't see any evidence at all of the impact that presumably caused it. They'll also see the evidence of a species with high intelligence, but of course that couldn't be the cause, because you wouldn't expect a highly-intelligent species to destroy its own ecosystem, right? So the extinction event will remain a mystery.

    • by evilviper (135110) on Monday July 12, 2010 @10:08PM (#32882836) Journal

      isn't this the most simple explaination? [sic]

      No, the most simplest explanation is that it's all an imagined phenomenon. A statistical anomaly due to selection bias, miscalculation, or vastly incomplete data-set... A ghost. Occam's Razor says so.

      • Re: (Score:3, Insightful)

        by 4D6963 (933028)

        No it fucking doesn't. Just because there's something you don't like doesn't mean you can pretend like it's not really there. "And their analysis shows an excess of extinctions every 27 million years, with a confidence level of 99%.". We're talking about hard statistical analysis, there's absolutely nothing that goes in the way of your bullshit "anomaly/bias/incomplete data" explanation.

        If your interpretation of Occam's Razor is "if I can't see why things are the way they are then they mustn't be like thi

    • Mily Way? Any relation to Felicia Day? I'd like to see HER bouncing up and down.
  • Are we not somewhere around two standard deviations out from the mean time between events since the last major extinction at the end of the Cretaceous? /me - thrashes for my copy of the Mayan calendar...

  • by Xtifr (1323) on Monday July 12, 2010 @06:49PM (#32881080) Homepage

    The second comment under the article seems to be a pretty serious debunking. I'm not going to take sides or tell you who's right and wrong because I don't know, but I will note that arXiv (the source for the claims) is for pre-prints and is not peer-reviewed.

    • Re: (Score:3, Informative)

      by mrsquid0 (1335303)

      The preprint has been peer reviewed and has been accepted for publication in Monthly Notices of the Royal Astronomical Society, one of the most prestigious astrophysics journals on this planet.

      • by GeoGreg (631708) on Monday July 12, 2010 @09:16PM (#32882348)
        Peer-review does not guarantee accuracy. In areas of evolving science, many papers are published in good journals whose conclusions are later determined to be in error. Some journals (I don't know if MNAS is one) are particularly willing to publish papers with novel or contentious conclusions in order to further debate on the matter.
        • Indeed! Peer-review is about judging the method of inquiry, not validating conclusions. There will always be alternative conclusions but it's the authour's perogative to choose the one they think best fits the evidence. The proper way to attack a particular conclusion is by presenting new evidence or better methods/logic in an opposing paper.
    • Re: (Score:2, Interesting)

      I read the comment. It seems to be mostly composed of reused commentary from the articles in question, unsubstantiated (and grammatically nonsensical) personal attacks on the authors involved in those articles;

      [Not to poison the well, but Bambach published lately in Ruse and Sepkoski eds "Paleontology at the High Table." One must take a dim view with the abilities of anyone that choose to cooperate with "philosopher of biology" and known stealth creationist Ruse.]

      and very little inf

      • by GeoGreg (631708)
        If you google around, you'll find stuff from Torbjorn Larrson (he's a Swedish ecologist, apparently) criticizing the data analysis in the original papers. He doesn't think they meet good statistical criteria.
  • Pathetic earthlings. Hurling your bodies out into the void, without the slightest inkling of who or what is out here. If you had known anything about the true nature of the universe, anything at all, you would've hidden from it in terror. -- Ming the Merciless

  • by ebonum (830686)

    A massive keg party held every 27 million years with everyone in the Milky Way invited! :)

    "Either way, the origin of the 27 million year extinction cycle is hotting up to become one of the great scientific mysteries of our time. Suggestions, if you have any, in the comments section please."

  • by by (1706743) (1706744) on Monday July 12, 2010 @07:13PM (#32881356)

    Sun's Dark Companion 'Nemesis' Not So Likely

    "Nemesis" is the codename for the next MySQL release, to which Oracle is giving the ax. After the 5.1 debacle [theregister.co.uk], I'm not surprised the database is being touted as a "Sun's Dark Companion."

    Odd, I just got this weird feeling that I'm being offtopic.

  • by magsol (1406749) on Monday July 12, 2010 @07:19PM (#32881428) Journal
    ...only it was a larger multiple: somewhere in the vicinity of every 150-180 million years. However, in this case, it's due to our solar system's z-axis oscillation with respect to the rest of the Milky Way galaxy. The dust and gas of the galaxy acts as a shield against cosmic radiation, but every 150-180 million years, our solar system reaches the z-edge of the galaxy and is maximally exposed to the elements.

    What accounts for the 5-7 other mass extinctions within that time frame, however, I defer to TFA.
  • by Trailer Trash (60756) on Monday July 12, 2010 @07:21PM (#32881440) Homepage

    It's been 26,999,998 years since the last mass extinction.

  • The articles second comment discusses in detail the idea of a 26M year extinction cycle.

  • I'd hate to think there was an 'orrible cunt out there seeking retribution against Sol.
  • by wealthychef (584778) on Monday July 12, 2010 @08:09PM (#32881724)
    Read the comment "Bad research, worse article" in the comments section. "Melott has made an arxiv carrier of various kinds of pattern searches and catastrophism scenarios in data. (What I would like to call "pseudoscience conspirationism".) " To sum it up, this article is probably sensationalist psuedoscience and there is nothing to see here.
    • by GeoGreg (631708)
      As another commenter here has noted, it's being published in a very high-profile journal. It may be contentious, but that doesn't mean it's pseudoscience. It may turn out to be wrong, but that alone doesn't make it pseudoscience. And conspirationism? Does he believe Melott is looking for conspiracy theories? Or merely drawing an analogy to the various types of data manipulation that conspiracy hunters use to "prove" their theories. I guess the latter, but it is something of a stretch. Rather than Torb
      • by RockDoctor (15477)

        which means it passed at least the smell test of some reviewers.

        ... whose purpose is to assess the described methodology ("Can I replicate this experiment from this description ; was the equipment used appropriately?"), not to agree with the conclusions presented.
        Unlike Slashdot, "I disagree" is something that they can put in their comments on the paper they review ... and they would still be expected to discount their lack of agreement and answer the questions they've been asked : does the purported statis

    • Re: (Score:3, Interesting)

      by RockDoctor (15477)

      To sum it up, this article is probably sensationalist psuedoscience and there is nothing to see here.

      Melott is a perfectly respectable palaeontologist ; Bambach I've read less of. But having RTFP [arxiv.org], I don't find it hugely convincing, nor hugely badly presented. Without spending a few days at least on reading up the background and working the statistics myself, I remain unconvinced in either way. (Which in no way reflects on Melott, Bambach, or Torbjorn Larsson.)
      Executive summary : different workers can't agre

  • by mevets (322601) on Monday July 12, 2010 @08:26PM (#32881838)

    Oracle, who are probably going to cause an extinction much earlier than this....

  • This question is more directed toward all you helio astronomers and astro physicists.

    Could it be caused by a solar event? Say, something like a Mini Nova where the sun undergoes a cyclical "hiccup".

  • Next week on the sci-fi channel the sun nemesis will strike!

    Why does this sound like that kind of movie but our super spy sat with a laser will save us!

  • by PPH (736903) on Monday July 12, 2010 @09:12PM (#32882294)
    ... Sun's dark companion was called Oracle. When did they change their name to Nemesis?
  • Seriously, it's a hella good book. Wiki has a good synopsis: http://en.wikipedia.org/wiki/Nemesis_(Isaac_Asimov_novel) [wikipedia.org]
  • As far as I can tell, a "small" body orbiting the sun at a period of 27 million years would have a semi-major axis of 1.4 light years. The Oort Cloud is supposed to extend to nearly 1.0 light years. A body with an elliptical orbit and large enough to seriously disrupt the Oort Cloud might perturb the sun to a measurable degree, or occlude stars such that it probably would have been detected by now, if it existed. IANAP though, and so probably have something wrong there.

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