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Linking Mass Extinctions To the Sun's Journey In the Milky Way
schwit1 writes "In a paper published today on the Los Alamos astro-ph preprint service, astronomers propose that as many as eleven past extinction events can be linked to the Sun's passage through the spiral arms of the Milky Way. (You can download the paper here [pdf].) From the paper: 'A correlation was found between the times at which the Sun crosses the spiral arms and six known mass extinction events. Furthermore, we identify five additional historical mass extinction events that might be explained by the motion of the Sun around our Galaxy. These five additional significant drops in marine genera that we find include significant reductions in diversity at 415, 322, 300, 145 and 33 Myr ago. Our simulations indicate that the Sun has spent ~60% of its time passing through our Galaxy's various spiral arms.'"
I only read the abstract, but while it proposes a correlation it did not speculate on the exact cause of the extinction. I wonder if passing 'nearer' (I use the term loosely) to higher concentrations of stars might disturb the Oort cloud, sending more comets than normal careening in towards the inner solar system ... or if we might catch stragglers from other stars' own Oort Clouds.
**might** be explained
Isn't that pretty much what "correlation" means?
Assume it were possible to slingshot our sun out of the galaxy into intergalactic space. Would we be better off there, or does the Milky Way offer some sort of protection against whatever's out there (radiation, etc)?
Better known as 318230.
So if we are moving through spiral arms, and it appears our neighbouring stars appear 'relatively' fixed to our position does this mean that all stars in our galaxy move through the spiral arms? Do the spiral arms move w/respect to all the stars like some sorta density wave?
A man spends the first half of his life accumulating stuff, the second trying to get rid of it all.
It means every time a mass extinction occurs on Earth, a galactic spiral arm is contructed.
All the tasty fish got eaten and overfished to extinction.
It's clearly global warming caused by man that has lead to these mass extinctions.
No. "might explain" implies a direction, nominating the transitions as the possible cause for the extinctions. Now obviously, there will not a a link in the other direction. But this still leaves the possibility that there is no link. Besides, even if there is a link, this does not really *explain* the extinctions until a mechanism is proposed/proven.
Given the inaccuracies on such measurements, there is no proof of correlation. The only thing they can claim is that they see an "alignment" in time between one type of event and another type of event at a totally different scale. This might still be coincidence (11 extinctions spread over several billion years, where even the authors admit that they see two different groups of 6 and 5 each.).
I know that's supposed to be tongue in cheek, but correlation is just another way of saying, we need to look into this with more detail. So if that's your hypothesis and there's correlation between the events, then who am I to judge if you decided to study it with greater detail.
It means every time a mass extinction occurs on Earth, a galactic spiral arm is contructed.
This sounds very reasonable to me, especially if it is just a "correlation".
So why are you calling it "rubbish?" They've found a correlation. That's interesting. No-one's claiming to have discovered the mechanism. Correlation is not causation. You seem to have inferred that because someone's found a correlation, they must also be claiming causation.
systemd is Roko's Basilisk.
So you're saying mass extinctions cause spiral arms? Interesting.
systemd is Roko's Basilisk.
Before you read too much into this report, remember that a preprint service makes papers available to researchers in the field before the paper has undergone the peer-review process. This allows the results to be circulated amongst other researchers quickly as the peer-review process can takes quite some time.
While not as bad as say having a press conference about discovering "Cold Fusion" before any peer-review only to find that the results could not be duplicated, take the papers contents with a grain of salt as the research has not been peer-reviewed.
You might think of it like the answers you get in the back of a textbook that have usually been done by an author's grad students. Most of them are probably correct, but nobody has gone over them with a fine-tooth comb to verify their correctness.
There has previously been a theory that these mass reoccurring extinctions would have been created by the near passing of a hypothetical star that we would have been unable to detect because it would be on the other side of the Oort cloud.
I suppose that this new finding will debunk that theory for good.
The hypothetical star had been named Nemesis. I know of it only because I ready about it in a novel by Asimov recently.
"We mustn't be caught by surprise by our own advancing technology" -- Aldous Huxley
in other news...many people die in hospitals, therefore hospitals may cause death.
And indeed they do.
http://www.health-care-reform.net/causedeath.htm
http://en.wikipedia.org/wiki/Hospital-acquired_infection
So don't be so quick to dismiss the possibility of causation, simply because it was discovered by correlation.
Falsely assuming no-causation is every bit as much as a statistics induced error as falsely assuming causation.
With correlation you have a reason to look for causation. Without correlation, looking for causation is just shooting in the dark.
Sig Battery depleted. Reverting to safe mode.
wacky waving inflatable arm flailing tubeman!!!
Politics is Treachery, Religion is Brainwashing
Is this some sort of inside joke? A reference to a Time Cube-style crackpot of whom I'm not aware?
Oh dear. I suspect you're serious.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
Because correlation is not causation and because they use the word "explain" Nothing has been explained.
The proper way to report on this would be to say that these extinctions "(appear to) coincide with ..." and that this may be sufficient ground for further investigation,
... is when we pass through the next one!
At best they have found a correlation in time.
So, you're saying they've found precisely what they claimed to have found -- a correlation.
"Convictions are more dangerous enemies of truth than lies."
By Sir Arthur Conan Doyle
http://en.wikipedia.org/wiki/The_Poison_Belt
Government cannot make man richer, but it can make him poorer. - Ludwig von Mises
http://news.nationalgeographic.com/news/2007/04/070420-extinctions.html Other researchers found that time periods Earth is exposed to large amounts of cosmic rays is correlated with mass extinction events. This is a possible explanation.
About 100MY for a big one.
Help stamp out iliturcy.
We use the most up to date Milky Way model and solar orbit data
in order to test the hypothesis that the Sun's galactic spiral arm crossings cause
mass extinction events on Earth.
That is how the authors of this paper reported their findings in the actual article's abstract. As for how some random Slashdot poster reported this idea, does it really matter? If you are complaining about Slashdot itself and lame editorship on the part of those who review these stories on the Slashdot staff, that is something else entirely and not something to complain about to the paper's authors.
Besides, they claim it is a causation, or that events which somehow happen during those crossings in turn trigger these extinction events. Unfortunately we have a data sample of one solar system to compare against right now to see if there might be any substance to the mechanism.
Well I'm not a scientist but with a little common sense being applied and knowing what we know it makes sense. After all what do we know so far? Well we know there is this HUGE band of rock at the outer edge of our system called the Oort Cloud, there is also another huge band of rocks in the inner system which may have been a failed planet. If going through the arm caused changes to the gravitational fields way out there in the oort cloud it probably wouldn't take much to get one of those chunks moving, after all that is where it is believed all our long term comets came from so there had to be something in the past that got the comets going. So if you look at how big a period we are looking at and how much debris we have in the inner belt the idea that going through the arm may occasionally cause one of those big inner rocks to get flung at us,possibly by being hit by something fling out of the oort? Really doesn't sound too implausible to me.
To me the thing I find really interesting is how many times our friend Mr Jupiter has saved us by being a big giant garbage collector and pulling all this crap into it that could have easily headed our way if it wasn't there. i honestly wouldn't be surprised if it turned out for every extinction event there was probably thousands that didn't happen because Jupiter sucked it up or slung it off in another direction,given how many times we have seen impacts in just the little bit of time we've been able to see that far out.
So I wish them all the luck, maybe if we can find out exactly what events cause these maybe we can avoid it happening to us, as while I doubt we'd see 100% fatalities of the human race one really nasty impact could easily send us back to the dark ages.
ACs don't waste your time replying, your posts are never seen by me.
A real test would be to use such transitions to look for another one not associated with any mass extinctions, and then go look if one actually happened.
I don't know if such would have lain undiscovered so far, but it would make for a good predictive test.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
I've got a novel by John Brunner written in 1982 called The Crucible of Time (), which documents a (very non-human) species through its scientific awakening. Throughout the book they're discovering that their planet is getting closer to a cloud of debris dense enough to massively devastate the surface, possibly shatter the planet. In the end they manage to build enough arks to save the species. The foreward reads:
"It is becoming more and more widely accepted that the Ice Ages coincide with the passage of the Solar System through the spiral arms of our galaxy. ..."
GStreamer - The only way to stream!
I agree with everything you wrote till this. Obviously a huge sub planet sized object and we are done. But something like a comet a few miles across how would that cause technological collapse planet wide? Lose 1/2 or 2/3rds of the population wouldn't do that. A technological regress requires a fragile society not just a sudden jolt.
Maybe an Electric Universe disciple.
Faster! Faster! Faster would be better!
It's been brought up before, and rather quickly debunked, not because a number of extinctions do occur at the periods of crossing a galactic arm, but rather the numerous other times when extinctions occur outside of the galactic arms, and the times it passes through the arms that the extinction events don't occur.
If you want to see what I'm talking about, just search the science sites about it.
Yes, it is an intriguing idea, but No, it doesn't hold up to scrutiny.
Thought I recalled reading something about this in Death From The Skies and sure enough, from over four years ago, Death from the Spirals! Maybe not so much. Given its age, I especially liked the punchline...
Are you sure it ins't closer to next Tuesday? I could swear that man on television asking me to send him money said it was next Tuesday.
Learning HOW to think is more important than learning WHAT to think.
Correlation is not causation, but correlation by itself does not rule out causation. Not sure why people have a tendency to discount that possibility. Is that an online thing, or does it happen in real life too?
I agree with you that there are probably gravitational perturbations to the Oort cloud or inner asteroid-belt that result in extinction-events but I also expect that there is another phenomena: the varying levels of cosmic rays as we pass through the galaxy's arms.
I don't know the meaning of the word 'don't' - J
You laugh, but in 50 years the atmosphere gets so hot that it excites the molecules to light speed, at which point it creates a rift in space time that tears back through time, sending hot jets of atmospheric gases ripping through the atmosphere and extinguishing life at periods in the past.
Also, the midwest will be completely covered in 200ft of popcorn.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
Mod Up. I remember reading about this when I was an undergrad 20 years ago. It's not a new hypothesis.
He can't be a man, 'cause he doesn't smoke the same cigarettes as me.
(making an account on slashdot just to get my parent comment noticed.)
And your link contains a pretty convincing refutation of the whole idea of the Sun having a significant surplus of charge. If it were true the solar wind would consist of particles witch charge of one sign moving much faster than particles of the other sign.
"The solar wind is a flow of protons and electrons, away from the sun, in all directions, both at the same speed. Now, if the first "major property" of the electric sun model were true, we would expect the positively charged sun to repel positively charged protons, and attract negatively charged electrons. That's what the third "major property" says is happening, but we see that reality is somewhat different. The observation of electrons & protons both being "repelled" by the sun immediately negates any consideration of the sun having a net electric charge that can be detected anywhere in the solar wind flow. If the sun had a net charge that was large enough, then it should repel one charge and attract the other, depending on the sign of the sun's excess charge. But we don't see that."
That doesn't mean what you seem to think it means. "Correlation is not causation" is a statement reminding people that "B causes A" and "X causes A and B" are alternative explanations to "A causes B" when one observes a correlation.
In this case, the only reasonable choice is "galactic orbit causes extinctions" or "the correlation is accidental"; none of the other alternatives are reasonable.
Statistically significant correlation between "A and B" almost certainly implies causation somewhere, it just doesn't always imply "A causes B"; "B causes A" or "X causes A and B" are the alternatives.
A competing hypothesis tries to show a correlation between mass extinctions and the times when our solar system is farthest to the "north" of the galactic disk. I've always found that hypothesis tantalizing and somehow compelling even though it cannot explain the KT event. Presumably there can be more than one cause of mass extinctions.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
Cosmic rays are from the cosmos, not from this galaxy. There is no reason to believe they aren't pretty much constant.
Areas of star formation are more radioactive due to massive blue stars and resulting supernovas when the massive star dies. More star formation happens in the arms.
https://en.wikipedia.org/wiki/Inverted_totalitarianism
Even those ejected by supernova and such?
https://en.wikipedia.org/wiki/Inverted_totalitarianism
I just went and tried to read the research. I couldn't understand a word of it, but it probably means the Earth is going to be consumed in a fiery cataclysm.
Just my luck this would happen when the Bears are 2-0 and my fantasy team is in first place. Well, I guess it's time to run up the credit cards.
You are welcome on my lawn.
Strong. Cosmic rays are just very high speed particles of different types, masses and speeds. Some come from extragalactic sources but the majority come from new stars and novas in the local vicinity. This data actually matches observations by Henrik Svensmark some years ago. He also observed correlation with the solar system's position relative to the galactic plane. The solar system moves up and down through the plane. Times when we are closer to lots of stars such as when we are in an arm or in the plane, correlates strongly with ice ages.
It's easier to be a result of the past, but more fun to be a cause of the future! http://www.spacefinancegroup.com/
A technological regress requires a fragile society not just a sudden jolt.
But we are a fragile society. Without even having to bring up the Idiocracy, the fact remains that we're mostly a society of specialists, dependent on the other cogs in the machine for our survival, stupidly mocking the "preppers" who are really just trying to be generalists. A comet strike could easily disrupt this machine and cause it to grind to a halt.
"Once we've identified and embraced our sickness, we'll have strength...and that's when we get dangerous." - John Waters
"Without catastrophic or otherwise challenging events, life seems to become complacent - evolution often plateaus."
And this is a bad thing... exactly how?
I think Idiocracy did a pretty good job of explaining why it's a bad thing.
"Once we've identified and embraced our sickness, we'll have strength...and that's when we get dangerous." - John Waters
While technology and technological knowledge could certainly weather a large portion of the population vanishing, what do you think of the economic implications of a significant impact event?
How would the global economy react to a mile-wide rock hitting Manhattan? Or Hong Kong? Berlin? Tokyo? Any large city?
I have the feeling that there would be a global economic upset the likes of which has never been seen.
Hectice, baby, Mercator says hello to you
the only thing that gets constructed is a lousy Vogon hyperspace bypass?
I almost took the time to create an account with Dolphin in the name to say: thanks for all the fish
New things are always on the horizon
Because correlation is not causation and because they use the word "explain" Nothing has been explained.
The proper way to report on this would be to say that these extinctions "(appear to) coincide with ..." and that this may be sufficient ground for further investigation,
"Furthermore, we identify ve additional historical mass extinction events that might be explained by the motion of the Sun around our Galaxy."
Where is the claim to have explained everything? I think there is an inherent suggestion in the above that further investigation is warranted. The paper does propose more than one possible mechanism, and I would guess that it could be that there have been more than one respnsible for historical events. I see this paper as merely saying that interesting stuff can happen when you're in a more interesting part of the galaxy.
I believe a mile wide asteroid destroys everything for about 100 miles and would be killing 200 miles on out. So for example a mile wide asteroid hitting New York kills most everyone in Philadelphia. So let's assume that happens. Note you are picking an almost worst case scenario with the eastern seaboard. We instantly kill say 20m people. GDP would drop a minimum of 10% but the dislocation is bad and say it drops more like 30% instantly (i.e. 27% per capita) That's an incredibly deep depression in the USA. So things are bad. Globally that's going to hit other countries in terms of trade. So UK, China... lose say .3*.2*.25 = 1.5%. We'll make it 2% drop for our trading partners so they have a normal moderate recession.
But... the we know how to fix supply chains. I'd assume we have growth on the order of 8% or more annually from that depressed level easily in the USA and similarly globally as we fix that dislocation. It might even be faster than 8% since 30% is such a depressed level.
A return to the dark ages would be something on the order of a 98% drop per capita that we don't recover from. You can see it is not even close.
Correlation does not equal causation but people tend to bring that logical point out forgetting that A correlation can be the causation. Toss a ball in the air, watch said ball subsequently fall down. Correlation. Connect an instrument to something, the reading is a correlation.
All of science is built on correlations and the assumption that the nature of reality is unchanging therefore things will behave tomorrow as they did today. So far it is mostly true. Things will probably behave tomorrow as they did today. The more we've seen them behave that way, the more correlations, the more probable that they will behave that way tomorrow.
And they say the Sun spends 60% of it's time there... it seems likely there are a lot of things that correlate to the sun passing through the spiral arms, at least 60% of the time!
The Dust Lanes of our galaxy are easily visible to the naked eye. But I speculate that the dust particles have sizes up to planet sized particles. In my book, "Dust Lanes", the Earth is hit by walls of rock from a dust lane with a relative speed of 5000 miles per second.
Carl Icahn put out a nicely worded take on why CEOs only promote people who are less intelligent than themselves...
http://gradspeeches.com/2008/2008/carl-icahn
It's amazing how over the decades you see the same stuff pitched as new over and over again isn't it?
No controls is kind of the point here. The sun spends 60% of it's time passing through these arms according to the summary. We have no way to change that and wouldn't if we could (altering the course of the sun seems like a "bad idea"). So what does this do for us? What do we do with it? Come up with a color system and give the current probability we are all going to die today due to events that are completely outside our control as a little colored bar in the corner on the weather channel?
How do they model the arms on the far side of the galactic center? There's a bunch of dust, gas and other stars in the way, and I don't remember there being a Cosmic Mirror out there. So are we making assumptions based on other galaxies, or do we actually have data for the far side of the Milky Way? If it's assumed, then why should we get excited over correlations found in an assumed model? And what does God need with a starship??
It was sad, we lost unicorns, mermaids, minotaurs, hydras and honest politicians.
*Repent!Quit Your Job!Slack Off!The World Ends Tomorrow and You May Die!
Is this the birth of the "Jupiter Vacation" hypothesis?
You'd think Saturn could pick up the slack for an eon or two, but maybe he's getting a bit long in the tooth.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
No, he said "rubish" as in "rubish cubed" or "as a rube would say"
He was a man who didn't know the meaning of the word "fear"; or the meaning of many other words longer than 3 letters
"Those who cannot remember the past are condemned to repeat it" -- George Santayana
Makes sense to me...there is more stuff to run into in the spiral arms than elsewhere. So when does our solar system wander through the next one?
In the quote from the top, I note that the end Permian mass extinction at 251 MYA and the K/T extinction at 65 MYA are not on the list. The first is the largest of the five largest ME's The one at 415 is on that top list as the Ordovician ME, which was less significant than the K/T one. It is the one for which a gamma ray burst has been proposed, which is controversial.
I haven't read the article, yet, but questions I would have concern how they define what the sun's motion in orbit around our galaxy encounters. Is it the crossing of the plane of the galaxy where problem objects might be more numerous or is it true spiral arms? I note the clustering of two events in the Carboniferous at 322 and 300 MYA, there is a major magmatic event in Siberia linked to those events and the massive erruption of the Siberain Trapps at 251 MYA has been implicated in the Permo-Triasic extinction. The sun takes about 150 MY to orbit the galaxy, so the authors would have to convince me that 1) they know the spiral arm configuration all the way around the galaxy and 2) that is it stable over 400+ MY. I might doubt that.
This story may be due to astronomers and physcists speculating about geologic and biologic events where alternative explanations are more likely. The geologic record in sediments and fossils for these events records changes in biota and changes in the chemistry of rocks, almost no direct evidence of an astrophysical nature. The Ir anomaly in the KT boundary is the sole exception. I am not sure what they might offer as evidence to look for. I assume that they would say the the earth would be a risk of encountering a nearby supernovae or gamma ray event. Would nearby energetic events leave something like different isotope ratios that can't be explaned by climate change?
Is it a correlation though? If the sun spends the majority of its time in such configurations, it should be that most events happen in this configuration.
The probability that it is just chance is 5% (lambda=0.6, k=n=6). So there is tentative evidence for a correlation at best.
NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
Is it a correlation though? If the sun spends the majority of its time in such configurations, it should be that most events happen in this configuration.
The probability that it is just chance is 5% (lambda=0.6, k=n=6). So there is tentative evidence for a correlation at best.
Does the Sun spend the majority of its time in such a configuration?
The problem is that the hypothesis that somehow the Earth itself and specifically mass extinction events on the Earth is the trigger mechanism for the creation of spiral arms in galaxies is suspect. Over the course of the history of the Earth, through the geologic record, mass extinction events are rather rare, but the paper in question suggests there may be some periodic nature to them happening. Suggesting that the mass extinctions are the cause of something still doesn't deal with triggering mechanisms in the event in the first place.... but if this hypothesis is correct it would be a wonderful indicator of life in the universe and substantially alter the Drake equation.
Of course I know it is a stupid hypothesis, but then the question that begs to be asked is why? It certainly would make for an interesting discussion among college freshmen, and those who think they understand science.
I almost took the time to create an account with Dolphin in the name to say: thanks for all the fish
You are not on reddit here.
Huh? Who was talking about the impact of losing a few specialities? I'm talking about a world where specialists have no value because the infrastructure isn't there to make use of them. You've completely missed the point.
And the other replies to your post are completely missing the point too. I'm not talking about going without high-tech hardware...I'm talking about going without FOOD. We can't go without food. And people wouldn't simply sit there and starve to death...they'll fight tooth and nail for the last scraps of food.
If being a prepper makes me crazy, I'm glad I'm not "sane" like you.
"Once we've identified and embraced our sickness, we'll have strength...and that's when we get dangerous." - John Waters
Well we know there is this HUGE band of rock at the outer edge of our system called the Oort Cloud
Last I heard, it was tought to exist but not confirmed. Visual tests failed to find this cloud since it's not shiny enough.
To push it further, I tend to recall it was hypothesized to exist since there are no other explanation regarding the origin of comets and asteroids.
In other words, I wouldn't say we "know", rather we "believe".
"The hallmark of humanity is the ability to move beyond sensory inputs" - Mary Helen Immordino-Yang