Sun's Dark Companion 'Nemesis' Not So Likely 306
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."
How long since last time (Score:4, Funny)
Re:How long since last time (Score:5, Informative)
Read the Fine Article.
We've got lots of time -- we're only 11 million years into this cycle.
Re:How long since last time (Score:5, Informative)
Re:How long since last time (Score:5, Funny)
Re:How long since last time (Score:5, Funny)
Wooosh
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Wooosh^2
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This isn't GameFAQs, you're allowed to say fuck
Re:How long since last time (Score:5, Insightful)
I predict a nuclear holocaust before then, honestly.
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Better use them now before they go out of style, then.
Re:How long since last time (Score:5, Funny)
Damn, and here I was, holding out that it would be December 21st, 2012.
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Re:How long since last time (Score:5, Interesting)
Better still, read the comment to the article by Torbjorn at the same URL as the article. Torbjorn calls it "Bad research, worse article" and he makes a pretty strong case.
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> Better still, read the comment to the article by Torbjorn...
I quit reading when I got to "stealth creationist". That's the sort of ad hominem crap that's typical of Slashdot comments.
Re:How long since last time (Score:5, Funny)
I quit reading when I got to "stealth creationist". That's the sort of ad hominem crap that's typical of Slashdot comments.
I quit reading after I got to the word "the". That's the sort of crap that's typical of Slashdot comments.
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But not of Slashdot commenters: you looked at the article.
Re:How long since last time (Score:5, Funny)
I quit reading after I got to the word "the". That's the sort of crap that's typical of Slashdot comments.
I quit reading after I got to Slashdot
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o yeh uwell i qwit reedeeng AND riting YEERS beefoor i got too slashdawt.
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True, but that doesn't make it right. And are you descended from a monkey on your mother's side of the family, or your father's side?
The person making the attack was a commentator on a blog which discussed the paper, not the authors of the paper (Melott and Bambach)
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11 million years (Score:2)
Re:11 million years (Score:5, Funny)
Crap, we're screwed. We are not good at planning ahead. If only we'd had more time.
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>>>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
Re:11 million years (Score:4, Insightful)
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...
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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.
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True but voyager is only 30 years old. More-over - it takes a society who has reached space-travel MORE advanced than ours to find it. If the moon can avoid a meteorite in the are where we left stuff - that has much better odds -but again, would only be discovered by a society the develops far enough to GET to the moon.
Right now - we could have missed it by just 40 years. 40 years out of 3 billion (the age of the earth) is a pretty damn small window and we don't have ANY evidence to believe we will still be
Re:11 million years (Score:4, Informative)
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)
At first I read "1.1 million years" and was really worried
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Yeah, I was hoping I could see DN4E first, too.
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There's no such thing as cancelled. It's just been postponed indefinitely.
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That might be enough if we have to run the simulations in Windows.
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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.
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>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
Re:11 million years (Score:5, Insightful)
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.
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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
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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.
Leave? (Score:2)
The Universe:
- Imports: None. It is impossible to import things into an infinite area, there being no outside to import things in from.
- Exports: None. See Imports.
- Population: None. It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Therefore, there most be a finite number of inhabited worlds. And finite number divided by infinity is as near to nothing as makes no odds, so the average
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Your logic is truly mind-boggling.
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From TFA: The last extinction event in this chain happened 11 million years ago.
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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.
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Here's hoping the universe isn't in a 1% mood, then.
Re:How long since last time (Score:5, Interesting)
From FTA:
There is a smidgeon of good news. The last extinction event in this chain happened 11 million years ago so, in theory at least, we have plenty of time to work out where the next catastrophe is coming from.
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in theory at least, we have plenty of time to work out where the next catastrophe is coming from.
... or make our own, with blackjack and nukes.
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Great. The suspense is going to kill us.
Re:How long since last time (Score:4, Funny)
Stress and nervous tension are now serious social problems in all parts of the Galaxy, and it is in order that this situation should not in any way be exacerbated that the following facts will now be revealed in advance.
The Sun's dark companion is in fact the legendary Magrathea.
The deadly shower of comets that will pass near Earth in a few million years will result merely in the breakage of three coffee cups and a micecage, the bruising of somebody's upper arm, and the untimely creation and sudden demise of a bowl of petunias and an innocent sperm whale.
In order that some sense of mystery should still be preserved, no revelation will yet be made concerning whose upper arm sustained the bruise. This fact may safely be made the subject of suspense since it is of no significance whatsoever.
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Don't make me woosh you.
Re:How long since last time (Score:5, Funny)
Cue the 2012 theories (Score:2)
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period of passing through the galaxy ecliptics? (Score:5, Interesting)
isn't this the most simple explaination? Most stars in Mily Way arms are known to bounce up and down the ecliptic.
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How exactly would that work?
The orbital period of Sol around the Galaxy seems to be almost ten times this extinction period.
Re:period of passing through the galaxy ecliptics? (Score:5, Informative)
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.
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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
Re:period of passing through the galaxy ecliptics? (Score:5, Interesting)
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.
Re:I am doubtful (Score:5, Informative)
Check out the Wikipedia article on the Oort Cloud. The Oort Cloud is thought to be well over a light year across. Out on its fringes the influence of the sun's gravity isn't much stronger than the pull of nearby stars, or the galactic core itself. So whenever the oscillation reverses direction and the sun begins moving back toward the galactic plane, a lot of stuff out on the fringes doesn't move neatly with it. Some of it will become gravitationally unbound from the solar system, but some of it will find its orbit perturbed and start heading inward. Whether that's enough stuff to lead to mass extinctions here on Earth is another matter.
This article mentions disk tides, encountered most strongly as the Sol system passes thru the galactic plane, as the possible culprit in disturbing the Oort Cloud on a regular basis:
http://www.americanscientist.org/issues/pub/perturbing-the-oort-cloud [americanscientist.org]
Re:period of passing through the galaxy ecliptics? (Score:5, Interesting)
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.
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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
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I, for one, will be building an underground city, you are welcome to join me Slashdot.
Hey, cool, thanks! I can bring guns, ammo, survival rations, a four-wheel-drive vehicle, electrical power generators and radio equipment and a Caterpillar D-9. But you're not allergic to cats, are you? Because I can't go anywhere without Fluffy...
Re:period of passing through the galaxy ecliptics? (Score:4, Funny)
Because I can't go anywhere without Fluffy...
Okay, do I know you?...
*sips coffee*
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Two times 27 (Score:2)
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...
Second comment debunks (Score:5, Interesting)
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.
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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.
Re:Second comment debunks (Score:4, Insightful)
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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
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Re:Second comment debunks (Score:5, Informative)
that's the third comment.
Here is a bit from the second comment:
Re:There is worse... (Score:4, Informative)
Some more debunking in the second comment:
First off, there is likely no "growing consensus that something of enormous destructive power happens every 26 or 27 million years". It is an old idea, probably originated with the terrible paper by Raup and Sepkoski 1986, which I have criticized on the web several times; (...) [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.]
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This is a complete fucking joke, and it's pathetic that you people are taking it seriously. Let's put things into perspective. The Earth's crust is about 5km thick under the oceans. It's about 3000km down to the outer core, with another 3000km down to the inner core. To say that this ridiculously thin crust is putting any significant pressure on that core is laughable,
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It's obvious, isn't it? (Score:2, Funny)
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
Cause (Score:2)
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."
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Right. The last one was on Mars, and look at the place now.
I think I understand (Score:5, Funny)
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.
BadAstronomer said something similar (Score:5, Interesting)
What accounts for the 5-7 other mass extinctions within that time frame, however, I defer to TFA.
By the way.... (Score:3, Funny)
It's been 26,999,998 years since the last mass extinction.
Read Articles Second Comment ! (Score:2)
The articles second comment discusses in detail the idea of a 26M year extinction cycle.
Well, I'm relieved. (Score:2)
Debunked nicely in the comments (Score:5, Informative)
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... 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. ... and they would still be expected to discount their lack of agreement and answer the questions they've been asked : does the purported statis
Unlike Slashdot, "I disagree" is something that they can put in their comments on the paper they review
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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
I thought Suns dark companion was (Score:5, Funny)
Oracle, who are probably going to cause an extinction much earlier than this....
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Next week on the sci-fi channel the sun nemesis wi (Score:2)
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!
I thought ... (Score:4, Funny)
Read Asimov's Nemesis (Score:2)
Nemesis (Score:2)
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No. Glaciation epsiodes have been happening fairly regularly for the past two million years or so. Before that the planet appears to have been free of ice ages for a few hundred million years.
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TFA doesn't think this is it either (Score:3, Informative)
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arent bunkers more about how deep you go, rather then how much surface area they have?
a two story bunker with x square meters is preferable to the same surface area in a single floor bunker even, as it reduces the surface area exposed to forces from above, which is where your threats are, bunker-wise.
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Seen Tremors?
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But ... ...
But
According to the books I've read, there is some poor guy chained to the Caucasus mountains and getting his liver ripped out by eagles every morning. Shouldn't we be sending out an expedition to free him first?
My source is probably newer than yours, so it's more likely to be accurate.
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Holy cow, 3600 goes perfectly into 27 million.