Earth's Biggest Disasters Strike In a Hidden Pattern Every 27 Million Years (sciencealert.com) 87
A new analysis of 89 major geological events over the past 260 million years found evidence that mass extinctions, volcanic eruptions, ocean crises, and other upheavals may cluster around a roughly 27.5-million-year cycle. The cause remains unknown, with possibilities ranging from mantle activity and orbital changes to speculative galactic influences. Slashdot reader alternative_right shares a report from ScienceAlert: One possibility lies deep within Earth itself. The planet's mantle is constantly circulating through convection, albeit at an almost unimaginably slow pace. Periodic changes in mantle convection, or the initiation of mantle plumes, could influence volcanism, plate tectonics, mountain building, and other large-scale geological processes. Because these systems are closely interconnected, disturbances originating deep within Earth could eventually ripple through the planet's surface, oceans, climate, and biosphere.
Another hypothesis focuses on interactions between Earth's surface and interior. Long-term orbital variations influence climate and sea level, periodically redistributing enormous amounts of water, ice, and sediment across the planet. [New York University geologist Michael Rampino] discusses the possibility that these changing surface loads subtly modify stresses within Earth's crust and upper mantle, potentially influencing tectonic and volcanic activity over geological timescales.
Rampino also considers possible influences beyond Earth, an idea he has been weighing up since the 1980s. As the Solar System orbits the center of the Milky Way, it oscillates above and below the galaxy's mid-plane, with the timing of these passages aligning with that of Earth's major upheavals. These crossings, other researchers have suggested, could also gravitationally perturb comets in the distant Oort Cloud, increasing the likelihood of large asteroid impacts.
Another, even more speculative, hypothesis suggests that if dark matter is concentrated near the galactic plane, a fraction of it could occasionally be captured by Earth. Over millions of years, this process could generate small amounts of internal heat, potentially influencing geological activity. At present, however, there is no direct evidence supporting either mechanism, so they remain very controversial.
Large asteroid impacts are discussed separately in the paper. Although they were not included in the statistical analysis of the 89 geological events, the timing of several of Earth's largest known impact craters appears broadly consistent with the proposed 27.5-million-year rhythm, as Rampino has discussed in earlier papers. Rampino suggests this correspondence may warrant further investigation, but stops short of claiming a causal relationship.
Another hypothesis focuses on interactions between Earth's surface and interior. Long-term orbital variations influence climate and sea level, periodically redistributing enormous amounts of water, ice, and sediment across the planet. [New York University geologist Michael Rampino] discusses the possibility that these changing surface loads subtly modify stresses within Earth's crust and upper mantle, potentially influencing tectonic and volcanic activity over geological timescales.
Rampino also considers possible influences beyond Earth, an idea he has been weighing up since the 1980s. As the Solar System orbits the center of the Milky Way, it oscillates above and below the galaxy's mid-plane, with the timing of these passages aligning with that of Earth's major upheavals. These crossings, other researchers have suggested, could also gravitationally perturb comets in the distant Oort Cloud, increasing the likelihood of large asteroid impacts.
Another, even more speculative, hypothesis suggests that if dark matter is concentrated near the galactic plane, a fraction of it could occasionally be captured by Earth. Over millions of years, this process could generate small amounts of internal heat, potentially influencing geological activity. At present, however, there is no direct evidence supporting either mechanism, so they remain very controversial.
Large asteroid impacts are discussed separately in the paper. Although they were not included in the statistical analysis of the 89 geological events, the timing of several of Earth's largest known impact craters appears broadly consistent with the proposed 27.5-million-year rhythm, as Rampino has discussed in earlier papers. Rampino suggests this correspondence may warrant further investigation, but stops short of claiming a causal relationship.
really shashdot? (Score:1, Insightful)
> "The cause remains unknown"
the cause is noise in incomplete, somewhat arbitrary data-sets.
but hey, at last some quack got a paper published.
"dark matter"? "the galactic mid plane"? I'm embarrassing for the people who review this shit.
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Yeah this isn't new either. I first remember reading this as speculation over a decade ago.
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Given your uid, probably on here as well.
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I remember how some of our professors used to fish out their old research papers, make some changes here and there with some
"new data" and "new perspective", polish them up and send them for publication. Mainly to meet their number of published papers per year department requirement.
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Yeah this isn't new either. I first remember reading this as speculation over a decade ago.
Actually, this was discussed already in the 1990s. Richard Muller used it to formulate his 'Nemesis hypothesis', whereby some large body on a (very ) long orbit kind of perpendicular to the ecliptic, would be behind such events. I don't think this gained much traction though.
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It may not have gained much traction, but that's because there's no real way to test it. Perhaps Rubin will find it (but it might be in the northern hemisphere). To me it seems much more plausible than most of the alternatives.
Nemesis hypothesis [Re:really shashdot?] (Score:2)
It may not have gained much traction, but that's because there's no real way to test it.
The way to test it is to find Nemesis.
There were multiple searches looking for Nemesis, all of which failed to turn up anything. There's a bit of a discussion in the book "Collisions", by Alec Nevala-Lee
https://unabridgedbookstore.co... [unabridgedbookstore.com]
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Yeah this isn't new either. I first remember reading this as speculation over a decade ago.
I remember reading this in the linked article about five minutes ago, so I believe your assertion of earlier speculation is true.
"The possibility that Earth's geological history follows a long-term rhythm has been debated for decades.
The idea dates back to studies published in the 1980s, when researchers first proposed that mass extinctions and other major geological events might recur at regular intervals. Earlier studies identified similar periodic patterns, but the idea has remained controversial."
A deepness in the sky (Score:5, Interesting)
Fascinating. According to this paper, previous major mass extinctions coincide with the sun crossing the galactic plane.
It is as if there is something about the location within the Milky Way that makes complex biospheres (or preventing major disasters) more or less likely. Zones of... something or other.
Or maybe it is just coincidence.
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previous major mass extinctions coincide with the sun crossing the galactic plane.
That's a hypothesis worth investigating.
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I read about it in a scientific report published ages ago, the title was "Currents of Space". It was, I believe, written by some unsuccessful chemist. Very readable, as far as those papers go.
Currents of Space (Score:2)
That title rings a bell.. I'll have to check it out.
"t was, I believe, written by some unsuccessful chemist."
Well he did get his doctorate in chemistry, in spite of not being able to produce thiotimoline.
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I think all of you are ov your rockers. ;D
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Fascinating. According to this paper, previous major mass extinctions coincide with the sun crossing the galactic plane.
It is as if there is something about the location within the Milky Way that makes complex biospheres (or preventing major disasters) more or less likely. Zones of... something or other.
Or maybe it is just coincidence.
This is plausible: at least from the "big impactors extinct things" perspective. As the sun orbits the galaxy, it also has a vertical oscillation about the galactic plane. So, a path like a horse on a carousel. We know this to be true, both from measurements and the way gravity works.
The galactic plane is a busy place, so close passes with other star systems will be more common. More bumps to things in the Oort cloud, more things zooming by earth, more big whacks that kill things.
The total amplitude of t
George Carlin was right (Score:2)
Planet will be here we'll be long gone, just another failed mutation,
Just another closed-end biological mistake
An evolutionary cul-de-sac, the planet will shake us off
Like a bad case of fleas
A surface nuisance
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The galactic plane is a busy place, so close passes with other star systems will be more common.
Not close enough to notice. Stars are very far apart. No, strike that. Very very far apart.
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And yet now and again, stars do come close enough to be measured in AU's instead of light years. Couldn't find the last article I read, though this talks about it and kinda disproves one pass, https://www.sciencealert.com/d... [sciencealert.com] and here's a more general article, https://www.astronomy.com/scie... [astronomy.com]
With stars, a close miss can still be bad and quite possibly when the solar system was young and still in its star forming nebula, close passes were common.
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The galaxy revolves around 250 million years.
So the solar system passes the plane roughly every 125million years, not ever 25 million.
Re:A deepness in the sky (Score:5, Funny)
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I believe the earth crosses the galactic plane every 30 - 34 million years.
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Nope, roughly 125 million years.
It's a conspiracy! (Score:1)
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The paper's author used their country's supply of red yarn, push pins, and straws. The follow-on paper will say how the Mayans were right and that they're uncovered the date and time of the apocalypse. Tin foil headwear: engage!
Nostradamus predicted this!
Late at night I sit
Scrying upon the night sky spectacle
Fireworks, we are all screwed
Burma Shave
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The paper's author used their country's supply of red yarn, push pins, and straws. The follow-on paper will say how the Mayans were right and that they're uncovered the date and time of the apocalypse. Tin foil headwear: engage!
Dammit, Charlie! There is no Pepe Silvia!
Shit journal - open-access - money grab (Score:5, Insightful)
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Data (Score:4, Interesting)
When I look at those spikes, it looks like there are a bunch of things that randomly want to kill us (like asteroids, gamma ray bursts, sudden changes in sea level, whatever, a bunch of other things), and they happen somewhat randomly with a normal distribution. Because of the way a normal distribution works, it will have some periodicity (ie, on average an asteroid will hit every X years, but with a deviation).
There is nothing special about 37 million years. That is the rough analysis [xkcd.com], and I saw nothing in the paper to convince me that is wrong.
Correlation is not nec. causation (Score:1)
It's not clear if the pattern-claimers have a statistical correlation or eye-balled it. If one runs enough variables against an events list, a coincidental match is fairly likely such that one should have grains of salt ready.
Those poor Permianites sure got whacked. There's some evidence it was caused by wayward volcanism, or at least volcanism was a contributor.
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Correlation is not a *sufficient* condition for causation, but it is a *necessary* condition.
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Did I imply otherwise?
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"happen somewhat randomly with a normal distribution"
Why would it be normal rather than some other distribution? That's actually significant!
"There is nothing special about 37 million years."
It's the mean of what you claim is a normal distribution. That's actually significant!
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I think your point is relevant, absolutely, but sometimes a cigar IS a cigar. Chaotic data *can* manifest patterns - eg a "random number generator" might hand you 5 results of 1-1-1-1-1. That may be the result of a *perfectly* random system.
OTOH, as humans we instinctively try to understand/recognize patterns to make predictive leaps. Chaotic data MAY ALSO have very subtle patterns that only appear when you start to do more and more statistical analyses.
The point is we can only take such data as a suggest
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So, this fixation you have of liberals' asses, you know there is a support group for you. Personally I find your fixation a bit extreme, but if it is what you need to get through the day, then have at it.
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No one knows more about gay sex than a white, Christian male.
The previous big disaster was 27 m years ago (Score:5, Funny)
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Not caused by dark matter, but orange matter.
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Kyoto University's LignoSat, the world's first wooden satellite, launched from the Kennedy Space Center?
Fourier analysis (figure 7 in the paper) (Score:5, Interesting)
Two considerations come to mind, however. The first is that this figure is based on 89 selected events, and while the criteria for those selections seem well-grounded, perhaps it should 62 or 117 events. In other words, have events been included that should not have been, or have events been omitted because they're not yet known? My own feeling is that as a first approximation this list is probably reasonable, but that it would be worth examining how including/excluding certain events changes this power spectrum.
The second of course is that this is an observation, not an explanation. There is no explanation, as yet, only various hypotheses. That's not really a criticism, a first step in understanding any process is to characterize the process as accurately as possible. I think a possible path forward here is to continue trying to do so without being overly concerned with the causative mechanism -- in other words, to try to understand that "what" as thoroughly as possible before delving into the "why".
Finally, I think it's worth remembering that when Alvarez et.al. posited an impact event 66 My ago as the proximate cause of a mass extinction event back in 1980, the very concept was difficult for many people to accept. We now do do because it's decades later and the substantiating evidence is overwhelming. Perhaps this is similar, and perhaps in time evidence will accrue that supports one (or more) of the explanatory hypotheses.
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It's quite interesting, because it definitely shows a signal -- and as the figure notes, possibly a second signal -- in the noise.
... this is an observation, not an explanation. There is no explanation, as yet, only various hypotheses.
It's further evidence we live in a simulation. The universe's random event timer(s) trigger, and random (often unfortunate) shit happens.
</troll>
My apologies, but since no-one else seems to have hypothesised the obvious explanation, I thought I'd do it. ;-)
Oops all space rocks (Score:2)
Although they were not included in the statistical analysis of the 89 geological events, the timing of several of Earth's largest known impact craters appears broadly consistent with the proposed 27.5-million-year rhythm
A great example of "proves too much". If your hypothesized pattern of geologic activity also explains the random trajectories of interstellar debris, it has no real predictive power.
Rampino suggests this correspondence may warrant further investigation, but stops short of claiming a causal relationship.
Oh sweetie, no. Claim it. At least embrace your woo.
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Maybe the author has it backwards, the geologic activity on Earth causes asteroids to pay attention and want to be here rather than there.
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" If your hypothesized pattern of geologic activity also explains the random trajectories of interstellar debris, it has no real predictive power."
If it makes predictions that match reality, it has predictive power.
You are assuming that that geologic activity and trajectories of interstellar debris are independent, and rejecting out of hand any root cause that could affect both.
But even before that, you are assuming that trajectories of interstellar debris are random and rejecting the existence of gravity.
Self organized criticality (Score:2)
89 data points (Score:2)
If you extrapolate from 89 data points, better not draw error bars. They are only confusing the reader.
The question no one is asking (Score:2)
When is the next one?
I'm about to head to the store and get some a) decaf b) dog food c) unleaded fuel for my brake lights (there was a video on YT but the title didn't really point out no scientific data e.g. brain fart, blonde moment, flat earther, wi-fi allergy etc)
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Don't hold your breath waiting for it. Even if this is correct, you can't expect it within the current millenium.
Personally I *do* favor the "Nemesis hypothesis", but there isn't any good evidence. And there isn't any contrary evidence. If it's in the southern hemisphere then the Rubin sky survey should record it, but actually finding it in that mass of data would be quite difficult, and it might be in the northern hemisphere. And we'd be looking for either a quite black hole, a neutron star, or possibl
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...The black hole would probably be hardest to see, since it wouldn't be expected to have an accretion disk. (If it did, we'd probably have seen it already.)
Why do you say it wouldn't be expected to have an accretion disk? The fact that we haven't seen it already isn't evidence.
"We don't know whether there are any kangaroos in my house. The fact that we haven't seen any means that they are invisible. How do we know that they are invisible? If they were visible, we would have seen them already."
The Earth... (Score:2)
...OG member of the 27 club.
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Duuuuude!
Interesting (Score:2)
So, if this is 89 events, how large is the probability of this being noise instead of an actual pattern? I do remember from statistics class that somewhat reliable hypothesis testing needs at least a sample size around 100. Hence this may or may not be enough.
And what about the model used? There have been too many instances in science where scientists found patterns that were not there, just because they had a huge (understandable) desire to find patterns. A newer example demonstrating the problem is the "D
Is no one asking the question? (Score:4, Insightful)
If these events occur every 27.5 million years, when was the last one? From that we can anticipate the next one and see what happens.
Since the paper is behind a cookie wall, I can't read it, but I don't see anywhere where the previous event is noted.
Re: Is no one asking the question? (Score:3, Informative)
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Randomness is a pattern, I guess (Score:3)
If you flip a coin a million times, you'll get heads extremely close to 50% of the time. If you flip a weighted coin, you'll get one side up more than 50% of the time. I guess you could call those outcomes, "patterns."
I you average the time between cataclysms, you'll get...an average. In this data set, 27.5 million years. When you take the average of *ANY* set of numbers, you will get a single number that's an average. That's how math works. It doesn't mean there is some magical, shadowy pattern we hadn't noticed before.
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" When you take the average of *ANY* set of numbers"
-1, off topic. That's not their analysis.
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I disagree. Their analysis does not show a clear trend that aligns with their average. There are just as many events in their chart that don't align, as do align.
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Well, half the events were "close" to the pattern (Score:2)
In the graph shown in the article, half of the events were "close" to the 27.5 million year pattern, but the other half were not. Maybe not so spooky?
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Sure if the events were independent and had a uniform distribution of periods, you'd still expect *some* to be close to each other. See "Birthday Pproblem": Given a sample 23 people, there's a 50% chance that at least two people have the same birthday. However, half of the sample being close to each other randomly is significantly less likely and it decreases as the sample size increases.
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It's debatable how "close" the events that align with the "cycle", even the "half" that appear to do so. Further, we don't have a complete data set. We have a non-random sample of events selected for this study. Both of those alone, could explain the apparent alignment.
To demonstrate alignment, you'd need to demonstrate, or at least suggest, a mechanism that brings about the alignment. No such mechanism has been proposed.
In any case, the sample size is way too small. If you flip a coin 89 times, you might g
Real, or false positive? (Score:2)
People have been looking for some periodicity in mass extinctions ever since the "Nemesis" hypothesis [space.com] some forty-plus years ago. The problem is that each study trying to find periodicity found a different period, depending on the details of what they counted as disasters and what they didn't. (For what it's worth, the recent biography of Luis Alverez, "Collisions", talks about the search for periodicity,)
I worry about this part: they studied "mass extinctions, volcanic eruptions, ocean crises, and other u
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"These are completely different things."
Unless they're not. Correlation may not be a *sufficient* criterion for causation, but it is a *necessary* criterion. Lack of correlation would mean you could stop looking causal relationship. There may still be no causal relation, but it would be absurd to reject on the *basis* of correlation.
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It should be rejected if it is a false positive correlation.
And, em, how long since the last one? (Score:2)
Planetary Phrenology (Score:2)
I know, lets feel the mountains to determine what is happening. Surely we can uncover all of Earths tendencies.
If another event hits sooner, do we recognize it? (Score:2)
Maybe those millions of years is just how long it takes this planet to recover enough for another event to register on a geological timescale?
Periodic Reawakening ... (Score:2)
27 (Score:2)
https://en.wikipedia.org/wiki/... [wikipedia.org]
Nemesis anybody? (Score:1)
This appears to be Nemesis again, which was postulated in the 1980s, but fell out of fashion as better data was obtained.
Somewhen out there, someone is late (Score:1)
Brain Wave (Score:2)
Science fiction novel by Poul Anderson, 1953 "Brain Wave" (https://en.wikipedia.org/wiki/Brain_Wave). The plot postulates galactic waves that dampen the effect of neurons. Mammalian life on Earth---including humans---developed within one of those waves. When the wave passed, humans and other life became much more intelligent.