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Is The Earth's Rotation Changing?
Roland Piquepaille writes "We all know about the current controversies associated with the ozone layer or the global warming phenomenon. Now, the NASA's Earth Science Enterprise (ESE) is warning us that atmospheric changes or El Niño events can affect the Earth's rotation. During El Niño years, for example, the rotation of the Earth may slow ever so slightly because of stronger winds, increasing the length of a day by a fraction of a millisecond. David A. Salstein, an atmospheric scientist from Atmospheric and Environmental Research, Inc., led a recent study about this possible effect. Salstein looked at meteorological and astronomical measurements from different sources and found they were in good agreement. Check this column for a synthesis. For technical explanations, images and animations, please read this NASA paper, Changes in the Earth's rotation are in the wind."
Great. So now can we have some lame movie made about it where they set off nuclear devices in the sky to get the earth spinning again?
This has been known since 1951.
I'll do it for cheesy poofs.
The days are getting longer? Cool, I could use an extra five minutes each day to read Slashdot...
Maybe it's because of all the people holding their breath over the PS3 coming out this year?
Txurlo
for example, the rotation of the Earth may slow ever so slightly because of stronger winds, increasing the length of a day by a fraction of a millisecond
And I thought the day only felt longer after eating at a Mexican restaurant.
People couldn't type. We realized: Death would eventually take care of this.
I wish Superman would get off his ass and do that whole 'spin-the-world' backwards so we could go back in time and prevent the term 'El Nino' from being invented - which so many bad stand-up comics have used to no end. Also, I would not buy my Voodoo 3 card.
I hate liberals. If you are a liberal, do not reply.
Yet another thing the greens can attach to (supposedly man-made) global warming.
this is really just a fake news to hype up "The Core", isn't it?
i get an extra millisecond of slep now!! woohoo. In 3600000 years i'll be an extra hour.
...since the poles flip/shift every few million years, it should be no surprise that rotation would suffer in the mean time.
By the way...when is the next pole shift due?
Just so long as it doesn't start spinning backwards. I dont' feel like going through my childhood again, especially not in reverse.
-
ping -f 255.255.255.255 # if only
I could use the extra time.
The alternative to limited government is unlimited government.
Physics tells me that a gas and a fluid have many similar characteristics. The most significant difference of course is a liquid is approximately 1000 times more dense than a the atmosphere.
Consequently the oceans slow the rotational period of the earth. I read about the physics of the tides twenty some years ago. The physics was clear then.
And for years, he had guests saying that the poles were going to shift! Oh no! They were right! We're sooo screwed.
I thought my work week was getting longer...
LFS. Have you built your system today?
It seems like a reasonable enough argument that the rotation period of the earth would change during an el nino period. But once this the el nino effect had ended the rotation of the earth would have to return to normal, so any effect that might occur would be only short term. Also due to the large difference in the mass of the solid earth and the earths atmosphere, the change in the earths period of rotaion would be so small as to be unmeasurable and therefore unimportant.
I can't wait til they add up and equal an hour. Just think an hour of extra sllep.
SCREW FLANDERS
Shuttle crashing, earth's rotation affected....
When did life turn into a Hilary Swank action flick?
Mod Karma -1: I sed bad wurds. If I cep my mouf shut, I wud be at riyses.
It's Kal-El Nino!
Big deal. Not only isn't this new "news", but it's been that way since the start billions of years ago. And here I was hoping that the article had some real information.
SSSsssshhhhhhh!!! Keep quiet. Or they might also notice that everyone has a free subscription to the bsd section. Every story there shows up with a red title bar!!!
I'll have something intelligent to add one of these days...
Everybody run east as fast as you can, to speed the Earth up again!
/me waits for hundreds of pedantic comments explaining why this wouldn't work
I'm living on the West coast and I'll happily see the sunrise now!
I'm sorry, but isn't this widely known? I learned about this effect in my 9th grade science class. Uneven heating of the surface can cause uneven wind resistance blah blah blah... and several million years from now, the day might be a few seconds longer.
Does simply adding the words "El Nino" makes people think this is a new, important idea? The planet's rotation speed is also affected by the impact of meteors and space dust, but I don't see anyone publishing studies to measure that infinitesimal effect.
It seems to me that whatever changes strong winds make in the earth's rotation must be temporary because of the conservation of angular momentum. When the wind pick up, the earth slows down. Wehn the winds die down, the earth speeds up again.
If you really want to get agitated about the earth's rotation slowing down, consider the moon. Tides act as a brake on the earth/moon system. So the rotation of the earth slows, and the moon (to conserve angular momentum) moves ever so slowly away from the earth.
Try moving towards the screen really fast. It should look green then. Of course, make sure you stop before you run into the screen, because a collision with a monitor at speeds close to the speed of light might hurt.
Still, with a plan, you only get the best you can imagine. I'd always hoped for something better than that. -CP
And what are you talking about with your statement about the change being "unmeasurable"? The point of the article is that it is being measured.
I hate liberals. If you are a liberal, do not reply.
Does it matter? We cant change it back
If this true, that the days will be longer...
I definitely have to renegotiate my dialy rate as a consultant... longer days = more pay !!
If at exactly 18:00 GMT today, every slashdot user simultaneously sprints due west, for the few moments we're all running, the rotation of the earth should be faster. Cool!
This must be Slashdot's news equivalent of watching wallpaint dry. OMG d00DZ EART ROTATIO SLOW d0N @ 1 MicROSeC0nDZ
increasing the length of a day by a fraction of a millisecond
Maybe this'll help catch up on sleep after staying up until 3am playing counterstrike when I have to get up at 7 for work....
"All great things are simple & expressed in a single word: freedom, justice, honor, duty, mercy, hope." --Churchill
The earth is already wobbling like a top that can't stand straight any more. Appearently it's suppoed to cycle every 26,000 years or so. This is supposed to account for Ice ages.
BASE Conflict for Quake 3
All this crap, including a bit I saw with a scientist going on about the "nuclear reactor" at the center of the earth is all studio-hype for "The Core", a movie sure to sink without a trace once it's released.
a little birdie told me
Did Mr. Patel invade his neighbor's house 12 years ago? And then lose a war against the rest of the neighborhood for it? And then agree to specific terms which he has now violated?
Yayy, more leap seconds!
When snow collects on mountains, it increases the earth's radius ever so slightly... so the actual day span increases by a fraction of a second. It's a small fraction though, but it still exists. This happens more during the winter when the earth is farther away from the sun. Anyways, it's nothing to get worried about. We've been dealing with rotational inconsistencies for awhile.
;
What's the average length of a day? Something like 23 hours, 59 minutes and 56 seconds or something like that. Which is why we have a leap year:
If the year is divisible by 4
Unless it's divisible by 100
But always if it's divisible by 400
So hey... leapYear = ((year%400)==0)||(((year%4)==0)&&((year%100)!=0))
Can someone answer this though: Do we manually synchronize our clocks every once and awhile (say every few years anyways) just to make sure? I heard a rumor about it (most people have to reset their clocks after the power goes out anyways, and PC clocks are horribly inaccurate), so is this true?
Could this be related to the Pole Shift on the next passing of Nibiru / Planet X?
-- Steal Me --
In what way is this a "warning". I can't think of any ill effects which could occur as a result of a day taking a few milliseconds longer.
I'd say its more of a "curiosity".
Not bad as trolls go. I give it a 5 out of 10. You should try to incorporate some kind of political or religious rant as well. That will get more people to bite.
we are a cancer on this planet and the sooner mother nature deals with us the better
Whether we destroy the Earth or the Sun does - it will be gone some day. The only chance that any of "mother nature's" creations have of getting off this rock is if homo sapiens carry them off. Otherwise, they're all doomed. We'll do the best we can but if we screw it up - so what? The Universe will not notice.
...due to the Moon and the Sun. On one day the rotation of the Earth will stop and as we only see one side of the Moon, only one side of the Earth will face the Sun. Once I calculated the time when the rotation will stop and I got about 5 billion years (assuming a linear slowdown). It's quite strange because that's about the remaining life of the Sun, too.
Government cannot make man richer, but it can make him poorer. - Ludwig von Mises
Is that really anything to worry about?
I mean having a day last 24 hours and a fraction of a milli-second surely won't alter evolution will it?
Though I'm sure our *smirking chimp* hasn't considered this, or any of the other implications of this massive stupidity we are embarked on.
You forgot to mention that you know Mr. Johnson and Mr. Patel are dangerous, because you sold them a couple of guns the other day.
I also can't help noticing that you can express yourself a lot more fluently than Mr. Bush. Perhaps you should have his job? I know I'd feel safer.
So the planet will spin a different yarn now!
Art Bell told me so. We are in trouble!
Well-known branch of astronomy called "LOD" or length of day measurements. Changes up to a millisecond or so each year. Atomic clocks and satellites allowed microsecond precision now. Weather, magnetic storms, earthquakes, ocean currents all tought to affect LOD.
I LOVE that phase! I first heard it from Rod Taylor in George Pal's version of H.G.Wells "Time Machine from 1960.
It is so elegant and so English. And no, I am not gay - I am more of a lesbian trapped in a men's body.
Just like the last one planted by the same folks. Who? its a promo for the movie "the CORE" about what? the slowing rotation of the earth's core (caused by a secret weapon project).
the last one was also in slash dot too. its was on drilling to the earths core with advanced materials. (sorry I cant locate the slashdot article right now, though I did see the last one about the mars core
in that case the movie distibuter's publicity folks were using real science and real information. They were just responible for planting news articles about it strategically. this smells the same, and the timing makes it clear.
Some drink at the fountain of knowledge. Others just gargle.
and other climatic changes certainly make the day seem longer
Get the EULA T-shirt
Wind can change the rotation of earth like losing hair can speed up my movements...
:))))
Reading this I have no questions left why Columbia did crash..
It seems everyone here is missing the main topic. (And not just the ones modded Offtopic)
The main cause of the earth's rotation slowing _during EL Nino years_ is the change in the angular momentum of the earth. This means, that as some point, the angular momentum will change BACK!! Hence, CONSERVATION of momentum. The net effect in the long run is no change in the earth's rotational period due to this phenomenon.
However, it has been a well known fact that the earth's day will gradually grow longer. One of the causes of this is the earth becoming tidally locked with the moon, the way the moon is now. It's just a function of relative gravitational force.
And offtopic: The geologic record does indicate the magnetic poles reversing every 10k-12k years. You'll have to research the 'why' on your own though. I only remember from my astronomy classes that it does...
The truth is out there, but the server is down or not responding.
If you two related things don't mean that the first named is the cause and the second one the effect, even if in theory one could make some impact in the other.
Okay ... so the days are getting longer, but what I want to know is: does this mean that I get to sleep a bit longer every night or do I have to work a bit longer every day??
as you dont seem to care much about anything and value yourself fairly low please remove yourself from the genepool, some other more caring people need the air to breathe. thanks.
If I recall correctly, earth rotation, in the beginning, was just 12 hours, and it's been slowing down mainly due to the tides.
It's funny because it's true !
Ok, damn offtopic and you deserve an offtopic mod, but still...
I'm brave enough not to post anonymously.
2. The interaction between Earth (solid ground plus oceans) and atmosphere can only exchange each participant's orbital momentum; it does not change the total orbital momentum.
3. Therefore, large-scale atmospheric phenomena can accelerate/decelerate the rotation of the earth on slow timescales (months/years). They have no influence on the long-scale deceleration (cf. point 1). The main point of the article is that one can use this short-time correlation as a test of measurements of the atmosphere and numerics: The fact that the two vastly different systems, namely the meteorological and the astronomical, are in good agreement according to the conservation of angular momentum gives us assurance that both these types of measurements must be accurate.
..to keep earth rotating in the good way!
What should I do with my life?
I think you meant the differences between gases and liquids. Gases are fluids. Liquids are fluids.
Of course, if your gases are liquid, you better check your underpants.
The well-known Liberal surveillance weather balloon that Liberals would have you believe to be the "moon" is held in its orbit by an intricate set of gravitational checks and balances to which the tides are integral. The "moon" has been shown by scientific experts to be moving further away from the earth as the tides grow slower over time, due to that, luckily, the Liberals who put the thing where it is failed to take the tides into consideration when they worked out the math controlling its movement, meaning the moon would eventually fall out of Earth's orbit, leaving God-fearing Americans once again free to exercise their Second Amendment Rights. However, the earth slowing down in its rotation would not change the rate of the rotation of the tides, due to Newton's laws of motion.
As we can see, the Earth slowing down will actually cause the moon to gradually become closer to the earth over time, eventually leading it to knock God-fearing Conservative anti-ballilstic-missle satellites out of orbit or-- even worse-- eventually strike the earth, ending all life on earth.
It is clear that this is just what the Liberals want. How did they cause this? The answer is obvious. The "Global Warming" myth was first perpetuated in 1979 (link) by the well-known Liberal, Margaret Thatcher from socialist Britain-- 1979, the same year that the tidal effect on the Moon was first discovered. It is clear that the so-called "global warming" effect was simply a straw man created by the Liberal establishment in order to have an excuse to put into place measures that would cause the slowing-down-of-the-earth effect needed to correct the mistakes in the design of their "Moon" weather balloon and cause the destruction of God-fearing Conservative satellites, thus increasing America's moral decay. Fact: This "El Nino" phenomenon did not take place once-- ever-- before the institution of so-called "anti-global-warming" measures such as the banning of CFCs. As proof, i point you to the last 80 years of "Time" magazine, preserved in my attic, in which El Nino is never mentioned prior to the 90s, even despite the well-known Liberal influences on the magazine.
I think the course of action is clear to all of us. I encourage you all to do your duty as americans, and do what must be done, about this moral scourge on God's Earth's natural rotation.
It appears the link between warming and rotation is pretty good. What is not good is the link between man's action and what appears to be part of the Earth's normal warming and cooling cycles.
Besides, I thought we were to all have died from Global Cooling by now, at least that was what they were saying in the 1970s. How did cooling switch to warming so fast?
Some months ago I saw an episode of NOVA which postulated that the moon has been gradually drifting out of Earth's orbit for many hundreds (thousands? millions?) of years. This causes the Earth's spin to be less uniform, to wobble. The more drastic the wobble, the more extreme are the changes in weather. I haven't seen anything else on this since, so perhaps it is not a theory that holds much credibility with scientists. On the surface, it seems to make sense.
First, I'm curious (maybe someone out there has a link?) about how solar wind affects affects day lengths. It's known and been imaged that bursts of solar wind cause the earth's atmosphere to swell, and I'm curious what this redustribution of mass does to the moment of inertia and rotational speed of the planet.
Second, I find it kind of interesting the change in the way we percieve time. Centuries ago, the earth made a great clock. 24 hours was defined as a day, and if all of the sudden the day became longer, that longer period of time was defined as 24 hours. Now, we see that the earth makes a pretty bad clock (by today's standards), and rather than relying on the earth as our ultimate timepiece, we rely on atomic clocks. It seems strange: we have all of these time units like hours, days, months, years, etc., all defined first by astronomical methods, but now because of our (technological) ability to be more regular than the cosmos, the hour, day, month, year, etc. have sort of lost their origins.
The best way to predict the future is to invent it.
all orbits have to have their own irregularities, I mean there's all kinds of gravitational fields that act on the the earth. not to say that the scientists are totally full of shit, but I'd say that it's a lot more likely that the rotation and orbit is changing the weather than weather changing the planet.
The World's Worst Webcomic!
Doesn't sound very impressive. If the change progressed much faster and the day got say, 1 minute longer in 10 years, would we notice anything?
More time for me to work on my TPS reports.
g
So if the earth's rotation has decreased, then there will be less centripetal motion acting to reduce the effects of gravity. That explains it. I thought I had just put on weight, glad to see there's a scientific explanation.
I am TheRaven on Soylent News
well one thing is for sure, you just promoted the hell out of that movie! ;^)
"solar wind affects affects day lengths"
:)
"on the the earth"
I thought this was restricted to speech, maybe the fingers are going to develop such problem?
Posting useless rant since 2003.
The Earth's oblateness (as measured by changes in the gravity field) has been increasing since about 1997. Speculation points to net movement of water from rapidly melting mountain and subpolar glaciers to the equator. One would suspect this would change the Earth's moment of inertia more than would changes in wind, but it is not mentioned in this most recent article.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
Yes, we still rely on those old and arbitrary divisions. But you know what? There /is/ a reason we kept them: they're good. An hour is a good amount of time to wait for something to happen. You could give or take a few minutes off of it, but an Hour really is a good length- much shorter, and you wouldnt be waiting long enough, much longer and you dont want to wait so long [for example, /three/ hours]
/man/ who decided how much to divide up.
See, these original divisions are based loosely on astronomy, sure. But it was
People who want to use a decimal-based system for dividing time are morons.
Obviously the above post is phrased quite poorly, but I do hope that I managed to get my point accross.
-- 'The' Lord and Master Bitman On High, Master Of All
The slowing rotation may also be affected by a change in the Earth's center of gravity. I recall from my calculus based physics class that if the mass of a rotating object is translated from near the center of rotation further away from that center of rotation, an object slows its rotation. This is known as conservatin of angular momentum. Taking all that crude oil from the ground and burning it in our cars over 100 years has shifted some the Earth's mass from below the surface to the atmosphere. And since there was a phase change in moving this material from the ground to the atmosphere, this should make the effect a little more noticable as the CO2 can be further displaced high in the atmosphere. This may contribute to a thousands of a second decrease in the Earth's rotation. Of course, I'm sure this guy also didn't take into account the umpteen million metric tonnes of star dust slamming into the Earth every year, adding mass to the Earth and further decreasing the rate of rotation.
I don't know, I just a geeky chemist with wild ideas.
Don't fart in a general direction, fart West.
Stop by my site where I write about ERP systems & more
i think its the other way around.
this might be an opportunity to make people aware of a real problem they wouldnt notice when not in the context of something fictional they enjoy spending time on (watching the movie). the problem is that, like with armageddon, when the mainstream media jumps on and the real threat is turned into a FUD spree. the research was done way before the movie but no one cared.
i got nothing
It appears to be written by the same screen writer as armegedon. Who losely bases his ideas on science.
You are a fucking hippie. We'll see who is right in 20 billion years... uh.. yea.
There is really no chance for anything or anyone. There is more of a chance for man than your beloved blue whales. Let's see them pilot a starship.
Ok, everyone, all over the planet...
...and ... EAST ... BLOW! ... WEST ... SUCK! ... EAST...
Face east, and...
BLOW...
now face west and...
SUCK
Shouldn't you at least acknowledge your source?
There's more of the same here and here.
Give us those error bars guys, than we can talk.
Sure information wants to be free, but how much are you willing to pay for the packaging?
El Nino isn't the root cause of the problem. It's that damn butterfly over in China again that's causing El Nino.
for that matter what about the minute changes that our orbit undergoes when we acquire more space dust (pounds and pounds a day) or send people/spacecraft into space. Losing or gaining mass effects orbit, too, in addition to meterological events.
this is not a sig.
Just wait untill we start generating power from the Earth's magnetosphere -- that should slow things down nicely.
All of these measurements are made under the purview of the International Earth Rotation Service. There are models for all manner of astrophysical and geophysical effects considered in the Conventions that are used when reducing the data.
The way that solar noon is kept at civil time noon is by inserting leap seconds. In most places civil time is offset directly from UTC. When a leap second is inserted the day is 86401 seconds long.
This irregularity upsets some kinds of timekeeping systems, and as a result there has been discussion that leap seconds should be abolished. That would cause noon to drift away from noon. That may not be a good thing.
I think a physicist (maybe Feynman) illustrated a similar fate, if mass numbers of people were to walk in westerly or easterly direction at the same time. Used in a lecuture to illustrate every action has an opposite and equal reaction.
Kinda like everyone in NYC flushing their toilets at the same time.
Either one would be a good cause to rally for, just for the sheer obsurdity it!
Another important factor that contributes to the slowing down of Earth's rotation is definitely space dust. Every year, the Earth gains at least 30 million kilograms of space dust. This added mass will indeed reduce the time it takes for the Earth to complete a rotation by fraction of a second.
We need a space vacuum to suck up all of the dust before it gets here...wait a minute, space is already a vacuum!
I've known this for eons. The earth's rotation slows down to a crawl every Monday, and then speeds up really really fast on Saturday/Sunday. Then it slows down again come Monday morning.
Earth weighs about 6 x 10^24 kg. We take about 4.5 x 10^12 liters of oil from a distance of 6,376,660, from the center of the Earth to about 6,378,160m from the center of the Earth (average oil well depth is roughly 1500m), that's .02% of the radius.
Somebody please do the math of how that would affect angular momentum.
Just because you don't want something to be true doesn't mean that it isn't true
And the reverse too. Of course they want global warming to be true, as they've based their whole being on that hypothesis. Disproving global warming to a green would be like disproving God to a Christian; both would result in a crushing blow to the psyche and massive denial.
Panic sells, and simply saying that the Earth has warming and cooling cycles doesn't. A lot of people have a lot to loose if it turns out the latest catastrophe fad is as valid as its predecessors.
I know all of that. What I want is something to show a causal versus casual relationship, and for someone to take into account the accuracy of measurements prior to the last 100 years.
Young-Earth creationists also use inaccurate historical measurements (in this case, the speed of light) to bolster their argument.
I would also like someone to explain to me why all the pre-1970 data used to show a cooling trend, and now it's a warming trend.
Basically, there has been too much chicken-little science throughout the ages for me to hitch onto a catastrophism theory this young.
The pressure at the core-mantle boundary is greater than 1 megabars (atmospheric pressure on the surface of the earth is about 1 bar). Temperature is greater than 3000 degrees Kelvin.
I can't wait to see how the movie works around this.
At least they don't have to worry about gravity as this remains relatively constant throughout the mantle (one the quirks of Mother Nature).
We don't live on a static planet in a static solar system in a static etc etc etc. Things change. When will the Scientific community just admit that constants only exist in tiny frames of reference? Cripes.
"I'm just here to regulate funkiness."
People need to realize that there is no such thing as a constant when we are talking about planetary physics.
Ice age(s) anyone?
Mod this guy down. He's passing bogus info (and I suspect he knows he's doing it.) Nobody who reads slashdot is so uneducated as to think the seasons are caused by the disatance the earth is from the sun. Nor that leapyear is related to inconsistencies in the 24 hour day. Our calendar contains a leap year because the time it takes the eath to complete one orbit around the sun isn't an integer number of days. He is posting bogus information and laughing at those who don't catch it (especially the idiots who modded him UP as "Informative"... come on people.)
Rotational speed matters not.
Consider precession , where the Earth's north axis slowly moves along the celestral plane like a slowing top, which changes what star we consider to be our "North Star." I believe Vega was closer to being the North Star some 15,000 years ago.
A more dire event: When the magnetic poles shift or trade places. That probably wasn't an event way back when except for migratory animals, but today with all of our electronics, it could be interesting to see what effect a shift would do to a computer or compass.
Or, maybe we should worry more about the Mets or the Cubs. Or if our martinis were shaken and not stirred...
Vos teneo officium eram periculosus ut vos recipero is.
The day is slowing down because of tidal drag from the Moon. Tides stretch the Earth along the Earth-Moon line; the Earth's rotation drags the axis of stretch around (about 45 degrees away from the Earth-Moon line, if I remember right). The asymmetrical shape pulls the Moon forward a little in its orbit, and the equal-and-opposite reaction (remember Newton's 3rd law?) slows down the Earth's spin by the same amount.
The Moon was certainly closer at one time -- Robin Canup, who works down the hall from me, has done some fabulous simulations of the formation of the Moon (thought to be from a giant impact of two planetoids; the larger fragment evolved into the Earth, while the smaller one became the Moon). She claims that Moon must have formed right around the Roche limit (the distance at which it would just barely not be pulled apart by tides). If that's so, then it would have had an orbital period of about 6 hours. Meanwhile, the Earth would have been rotating faster yet.
The ongoing tidal drag is evident in the "leap seconds" that some international committee periodically adds to atomic time to get coordinated universal time. The leap seconds are becoming more frequent, because (surprise) the day is slowing down a microscopic but measurable amount compared to its speed in 1951. (One leap second per three years corresponds to a proportional change of only 1 in 10^8 [100,000,000], so no wisecracks about sleeping in late, please!
Well, High School Chemistry I taught me that gas is a fluid.
The three states are Solid/Liquid/Gas - and there is also a thing called a triple point at which all three can exist at the same time.
I do not fear computers. I fear the lack of them. Isaac Asimov (1920 - 1992)
Earth's rotation is also found to be affected by bad breaths created by the geeks of the North America. For example, during the dot-com boom, Earth's rotation was found to be slowed down by a fraction of a microsecond.
Apparently geeks from other parts of Earth did not contribute to the slowdown. Experts suggest that it might be related to the discrepancy of bad-breath/good-breath ratio among the populations.
Any sufficiently simple magic can be passed off as mere advanced technology.
This bug has been confirmed by Microsoft and they are currently researching this problem. Don't expect a quick fix, since the last time the support article was updated is Oct 1999.
The Danish countryside is littered with white wind turbines. One day I noticed they all point in the same direction. I always thought they were trying to produce a cool breeze to compensate for the global warming, but now I know they are actually trying to control the spinning rate of the earth. Who would have though?
In Murphy We Turst
Actually the earth is slowing down regardless of weather phenomena, etc.
It is a known fact that the earth is slowly transferring its axial momentum to the moon. The earth is spinning slower and slower (granted by extremely minute amounts) while the moon orbits faster and farther away (also by exremely minute amounts)...
Sadly, the fact that gasses (identically to liquids) can create drag on any body within them is far from new, startling or amazing.
In fact, here are a few other trivial points:
None of this stuff is outside the scope of an A-level student taking maths and physics. The chances are, though, they won't get 5-figure paychecks for coming up with such trivia.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
is to attach giant rocket engines to the side of the planet, facing due west and due east. We can fire them periodically to recalibrate the length of our days. Then the environment will be safe!
You see? You see? Your stupid minds! Stupid! Stupid!
If the Earth were the size of a billiard ball, the atmostphere would be about the thickness of the paint on the ball. This has always given me the impression that nothing happening in the atmosphere could have much physical effect on the planet. The change of a millisecond per day is definitely small.
The conservation of angular momentum should make this effect temporary, shouldn't it? As has been pointed out above in comments, if everybody ran West the Earth's rotation would speed up, but as soon as we stopped running it would return to what it was before. I would think this would hold true for wind effects as well.
Some say a comet will fall from the sky.
Followed by meteor showers and tidal waves.
Followed by faultlines that cannot sit still.
Followed by millions of dumbfounded dipshits.
Maynard said it best... "Learn to swim, I'll see you down in Arizona bay."
Earth's rotation is also found to be affected by bad breaths created by the geeks of the North America. For example, during the dot-com boom, Earth's rotation was found to be slowed down by a fraction of a microsecond.
Apparently geeks from other parts of Earth did not contribute to the slowdown. Experts suggest that it might be related to the discrepancy of bad-breath/good-breath ratio among the populations.
http://www.amazon.com/exec/obidos/tg/detail/-/0380 792923/qid=1047317943/sr=8-1/ref=sr_8_1/103-650771 8-2230237?v=glance&s=books&n=507846
it's the French's fault.
I remember hearing some years ago that if everyone on the planet all walked in the same direction at once it could affect the rotation of the Earth. I've always wanted to do the calculation but I haven't bothered to find out how much force your foot applies during a typical step. Anyone know? We can figure out how much torque and therefore change in angular momentum together! Woo!
Here's a thought: Remember in lab class when your teacher spins on a stool and sticks his arms out and slows down? What about all the construction/building going on around the planet, moving mass farther away from the center of the planet(skyscrapers, bridges, etc)? It must have some tiny effect.
Thinking about this with my limited knowledge of Earth sciences, isn't it at all possible that the weather patterns are caused by, rather than causing, this phenonmenon?
Resistance is futile. Reactance buggers it up.
I think the best way to counteract this effect is to have all the members in congress sit in the same direction opposite of el nino.
Did someone mod this "insightful"? Wow.
Everyone knows God's creation sits at the center of the Universe and it is the universe that rotates! Foul heatens deny it but they have been blinded by Satan!
I never spellcheck and I freely admit it. Save your karma for more worthwhile "lol erorrs" replies
of the old sig
Earth rotation is created by penguins running around the south pole.
The rotation of the Earth is very easy to measure, just note the exact time when a distant galaxy crosses a reference mark in a telescope. However, scientists being able to measure something doesn't mean that it's relevant.
Have you ever worried about who is responsible for making sure the Earth is rotating? Check the International Earth Rotation Service website.
I beleive that while the ozone may play a part in global warming, the earth's orbit is also losing area each year, also adding to the effect. Wouldn't that also cause the orbit to slow? More drag the closer it gets to our gravity monster?
Wouldn't 1 cm make a difference? I dunno, its just an idea.
How do they measure distance from the sun anyway.
Maybe not for the reasons sited, but lets look at some of the most basic laws of physics (or corrolaries thereof):
Objects in motion tend to stay in motion unless acted on by another force.
For a given mass and given energy, an object will spin at some calculated rate
Every force has an opposite and equal force
From that is seems we can plainly draw these conclusions:
There are forces slowing it down: gravity from the Moon and Sun, friction from the gasses that surround the planet (atmosphere and cosmic). It may take time for those minute forces to stop the Earth, but the eventually should.
Each year the Earth is bombarded by massive amounts of dust, particles and meteors from extraterrestrial sources. This all adds to the mass of the planet. Since there is not external force to add more rotational energy, it makes sense that the planet would need to slow down as it gets both more massive and larger in diameter from the addition of this material.
There's also the known fact that the Earth's magnetic field changes (swaps) every 250,000 years or so. North becoms South, and vice verca. This change may very well have a significant impact on rotation and orientation of the axis of the planet. (Some scientists say there is evidence that we are in the midst of such a swap now and the event could occur during this millenium)
Whether these effects will lead to significant changes in rotation during human's habitation of the planet, or the sun will die out and engulf the inner planets first, I don't know. In either case, I'd say it's high time we (as a species, not as a country or countries) stop finding reasons and ways to hate and kill each other, and try to find ways off this little rock.
Article X: The powers not delegated... by the Constitution...are reserved...to the people
In fact, since hot objects radiate, and radiation carries angular momentum, the angular momentum which is stored as heat eventually radiates away from the ball-sheath system, and is lost forever.
That means that SUV's are messing up the spin of the entire universe. Butterflies have also been observed flapping wrong because they are too hot. That'll really mess things up. What have we done!
Table-ized A.I.
It was prophesies by the Prophet Muhammed (peace be upon him) that the Sun will rise from the West 1400 years ago. And this is the early sign of it.
The Earth rotates at the "and you turn yourself about" point, when the turtles do the Hokey Pokey.
The REAL jabber has the user id: 13196
What you do today will cost you a day of your life
By cutting down all those trees, we're reducing the friction of the Earth, causing it to spin faster. It's all a self correcting system, you see...
The REAL jabber has the user id: 13196
What you do today will cost you a day of your life
Goddamn! I got a ton of homework and I'm never ever gonna get it done tonight!
Is there any way we can make the earth slow down some more, really really *quick*?
Momentum is not energy. Angular momentum is always conserved. Just think about it logically - to slow the rotation of an object down it has to push against another object in the opposite direction of rotation - which increases the rotation of that object. The sum total of angular momentum (similar to linear momentum) will always remain the same. This is very basic physics people.
Water spinning in a bathtub will eventually slow down as it transfers its angular momentum to the tub (and the planet itself). But the earth is in a vacuum, there's nothing to transfer the angular momentum to.
A quick link grabbed from google on the subject.
Something i find even more disturbing is humanity's influence on the degree to which the earth wobbles as it rotates - according to a piece in Scientific American last year (couldn't find the article on theirr site), dams and resevoirs have displaced such a huge mass of water that the degree to which our planet wobbles on its axis has noticeably changed.
I bet if everyone in the world faced the same direction and farted at the same time we could go back in time.
I'm sure they work around it like any good Hollywood summer blockbuster: by ignoring it!
Come on, you didn't think that The Core will be a serious scientific movie, did you? We get to see lots of cool CG effects, probably some kind of sappy love story, and lots of explosions.
Well, I am pretty sure I've heard it said that the moon slows us down. Forgive me if this has been pointed out a dozen times already, but I didn't see it as I read thru most of the posts. So, given fact that the moon slowly slows us down - the whole energy loss during tidal surges and everything...Could it be simply that we are miscalculating the effect of the Moon? Or better yet, increased polar cap melting putting more water in the oceans, so we have more tidal effect slowdown of the earth's rotation?
Who is this that even the wind and the waves obey Him? Surely this computer must submit also!
Also, the length of a siderial day (less than 23 hours) is not why we have leap years, though it is somewhat related. We have leap years because there are not exactly 365 days in a year.
Actually, you can also calculate the earth's siderial period for yourself. You know that a year is roughly 365.25 days long, with the extra 0.25 days coming from the 1 in 4 leap years. The earth turns once relative to the sun in almost exactly 24 hours (by definition), but once per year we revolve once around the sun, effectively getting one more rotation relative to the universe for free. Thus, the actual length of a day is:
This is still not entirely accurate, but it is within 1/10 second of the actual value.Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
The evidence is only that when the earth slows down the winds appear to be faster. This is not a causal relationship only correlated.
For instance it could be that the earth is slowing down independant of the winds thus causing the winds to increase in speed. Eg. the relationship proferred by these scientists could in fact be the exact reverse.
Or in fact they could have nothing to do with eachother and simply be the observable affects due to a third unlooked at phenomenon.
Sure information wants to be free, but how much are you willing to pay for the packaging?
We would have to keep the second because so many other units have time in seconds as a term. Building up from seconds by powers of ten isn't all that unnatural. A centasecond is 40 seconds longer than a minute. That isn't too bad, it's about half way between a minute and two minutes. It still works for "give me a minute" type situations. Going beyond that, it gets really hard to fit it to the day. Sure, the astronomical phenomena the usual calendar is based on are slowly changing but they'll still fit pretty well on timescales in the thousands of years. So yeah, it would be stupid to change that on Earth.
If however we leave the Earth in significant numbers and I'm not holding my breath, then it won't make sense at all to tie time to a planet you haven't been to you're entire life. Earth based time wouldn't seem very sensical to even a Solar System spanning civilization. If Mars, planetoids, and gas giant moons are inhabited then decimal time starts looking pretty good. The orbital and rotation periods of any one body will be arbitrary to any other.
Decimal time would then serve the same purpose Railroad Time used to serve. The inhabitants of a particular body can use whatever local standard they wish and the Decimal standard for intrasystem use.
Of course, it will be hundreds of years at least before we have to worry about any of this. If we have to wait on NASA better make it thousands.
Everything changes. Why is it that it's such a big surprise when we discover the possibility that there is flux in this, that or the other thing in nature? Just because we needed specialized instrumentation and technology to detect it, why should that mean that it's so unimaginable in the first place?
For your security, this post has been encrypted with ROT-13, twice.
I read that Atlanteans modifying the earths weather through the use of magnetic or gravitational control. The controlling device's misuse threw the earth off its rotation, causing widespread destruction. Some of the Indians (mayans maybe?) had documented in their drawings of people narrowly escaping that destruction by leaving earth on ~flying turtle shells~.
...it flaps instead!
If everyone faces west and blows as hard as they can, maybe we can speed up the Earth's rotation a little and solve the problem.
Vote for Pedro
They don't blast much matter into orbit, do they? When the matter comes back to earth, won't it cancel out the rotation? Say a volcano is pointed west, it launches a big glob of magma westward, speeding up the earth's rotation. The big glob of magma is travelling opposite to the earth's rotation. When it lands, it transfers momentum back to the earth, slowing it.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
I knew the damn days were lasting longer during that el nino year. I tried to tell people, that the days were clearly longer, but they all thought I was crazy. Who's crazy now bitch?
If I'm not mistaken, thats also about the estimated time until our galaxy collides with the Andromeda galaxy. So we're screwed.
Maybe this is nothing to worry about by itself. But if it does turn out that the underlying cause of the change does happen to be man-induced climate change, those climate changes may have serious consequences. So its important that we study and try to understand this stuff anyway.
Sheesh, this is NEWS? The earth is an open system: that's been
established _repeatedly_ now. The energy coming in from the Sun
(and trace amounts from other sources) is not without effect, duh.
So of _course_ stuff changes. Yeah, the earth's rotation changes,
its inclination to the eccliptic changes, it's orbit changes, its
mass changes, the distance to the moon changes, the composition
of the atmosphere changes, the chemical content of any given
rock changes, et cetera. Uniformitarianism is an interesting
idea, but it doesn't jive with the real world.
Next they'll be reporting that the English language changes too...
Cut that out, or I will ship you to Norilsk in a box.
Incidentally, with uniformitarianism thoroughly discredited,
that means radioactive-decay dating methods are unreliable.
But we already knew that, too.
Cut that out, or I will ship you to Norilsk in a box.
I guess that's why the Chinese have planned a moon mission - they're going to destroy it so our descendants millions of years from now don't have deal with the inconvenience of 24 1/2 hour days.
They're going to be smart in the future, but how the hell would they mark a clock like that? Thank the Chinese for preventing this catastrophe.
I saw a screening already.
They come up w/ a fantastic new material to get around the heat and pressure to the external of the ship. "the actual name has 37 syllables, I've been calling it unobtanium"
i guess you have to let the art flow over you.
the movie was OK, tried to explain some of the science but assumed most of the audience would be looking for loud things rather than worry about thermodynamics. "the liquid core is like an engine, it only takes a small wrench to stop a big engine" sums it up pretty well.
ej
We could all go live closer to the poles, build dams to keep the water toward the poles, freeze water on the poles(a good nuclear winter), or drop heavy things into the deap parts of the ocean.
:)
The problem is, global warming melting the polar ice caps will cause more water to shift toward the equator, this slowing down the rotation of Earth yet more.
By the way, they are only saying that El Nino periods could have longer days right? This couldn't be a permanent thing could it? Or are the winds so strong they are breaking out of Earths gravity?
On a side note, doesn't global warming pose a much greater threat to increasing the length of the day than wind? If the polar ice caps melt, all the water will end up near the equator. Energy will need to be added to this water in order to get it up to the speed of Earth's rotation.
Mining minerals seems to me like it would cause more of an effect (since this effect would be lasting).
Karma Clown
Dude, I said NT.
I think it would make everyone's ears pop as well.
http://en.wikipedia.org/wiki/2004_U.S._Election_c
enough said.
It takes a big man to cry. It takes an ever bigger man to laugh at him.
Science advances one funeral at a time- Max Planck
Does anybody listen to what I have to say?
Science advances one funeral at a time- Max Planck
We need nessus to aim a solar flare at the remaining attitude jets to put us back into the correct position! Hurry!
The new mega dam being built by China (Three Gorges Dam, I think it is called) will cause enough of a backlog of water to play with Earth's spin and thus help lengthen our day. But I guess you'd have to be really sensitive to notice it, or live to be reaaaaally old and annoying about it ("Why, I remember a time waaay back in the 20th century...")
Mmmmmm... Bold, yet refreshing!
The earth's rotation has a certain precession to it like a top that starts out spinning perfect and then starts to slow and thus lose it's inertia. This will have all kinds of affects on weather among other things...
||| I still can't believe Parkay's not butter.
We should BLOW UP THE MOON! Yes, another reason to further nuclear research!
hehehe....I hope this will soon introduce a bug in computer clocks!!!
Last time such a bug appeared, I made a bundle as a consultant debugging millions of lines of code, to make sure the programs would pass the new millenium
It has nothing to do with the weather. The massive concentration of 7200 RPM drives in the Northern Hemisphere is diverting our precious angular momentum into spinning disk platters.
To counteract this phenomenon, we must get half of the drives rotating in the opposite direction. If your IP address ends with an even number, remove your disk drive and turn it upside down immediately.
---- "If we have to go on with these damned quantum jumps, then I'm sorry that I ever got involved" - Erwin Schrodinger
will a millisecond-longer day really matter? will the average person even notice? who really cares?
Conservation of angular momentum.
All you need to do is put away a few stiff drinks and everything will be rotating just fine.
IAAL
You bastards! I spent a lifetime worth of slowdowns just reading the bloody post. ;)
Some people have a way with words, and some people, um, thingy.
I do like how they pulled a paper from the CATO institute to support their claim that the ice age was an invented scientific myth by the likes of Paul Erlich.
They forgot to mention that the paper as a whole did a very good job of equating the 1970s myth with today's. Thanks for pointing me indirectly to that paper, very informative.
Don't forget, we were all supposed to not only have frozen by now, but also to have died by mass starvation in an atmosphere of chaos. I don't have anything against a theory of global warming in itself, but I am extremely skeptical of Erlich and others who use panic-driven publicity to devise another method of gaining power.
Of course, first you have to define uniformitarianism. If you wish to construct a strawman argument, for example, you would define it as meaning 'everything stays exactly the same forever'. If you wish to use a definition which makes sense, you take it to mean 'The laws of physics are constant and can be used to exalain Earth processes in the past'.
So we can say that stuff changes - but that does not give a carte blanch to insert whatever idea you want.
There are forces slowing it down: gravity from the Moon and Sun, friction from the gasses that surround the planet (atmosphere and cosmic). It may take time for those minute forces to stop the Earth, but the eventually should.
And you might be interested to know that we can even measure this; it's in the order of 40,000 tonnes/year. Total mass gain since the end of the late bombardment would come out at 0.0000000027 times the Earth's mass. The estimated time for the Earth/moon system to become tidally locked is 40 billion years, assuming the system still exists. The moon will then get close enough to break up into a ring after another 60 billion years.
There's also the known fact that the Earth's magnetic field changes (swaps) every 250,000 years or so. North becoms South, and vice verca. This change may very well have a significant impact on rotation and orientation of the axis of the planet. (Some scientists say there is evidence that we are in the midst of such a swap now and the event could occur during this millenium)
Right, just one question: How the f**k does a change in the Earth's magnetic field (yes, that field which can tell you which way is north, as long as you are not too close to a bl**dy fridge magnet) have the slightest impact on the rotation axis of a planet the size of the earth? This may sound like a rant, but I've heard that idiocy repeated ad nauseum...
Unless I'm mistanken, the earth has been slowing down as the moon is pulling further away. (Preservation of angular momentum),
:-)
I expect that the researchers have done their homework, and that this is a factor they've taken into account. No I haven't read the article, so
sue me.
A witty
The only spin worth noting here is the publicity spin on a well known yet hidden fact in science that the earth spin is not only slowing but will eventually come to a stop. The most obvious evidence of this is the tilt on our axis. What object spins on its axis which happens to be on a tilt without eventually coming to a stop. Just go spin a top and you'll understand what's going on with the whole terran spin.
CATO has papers for everything, not just economics. They do no scientific research in these other areas, but they are very good at pulling together the existing research, admittedly with a litertarian bias.
If there is such a scientific unity on the subject, why did 15,000 U.S. scientists sign a statement against the Kyoto Protocol saying that the available data do not support the computer climate models being made? This is a sharp contrast to the 2,500 scientists supporting the IPCC position (however, on both sides, not all scientists were meterologists or in related fields).
Then there's also the 4,000 scientists signing the Heidelberg appeal to the Framework Convention on Climate Change meeting in Rio, warning that the science didn't support such a treaty.
See also the Leipzig Declaration signed by scientists from institutions all over the world, including MIT and Max Planck Institute for Meteorology.
In addition, the popular face of the IPCC, and the UN's own take on the findings of the contributing scientists, are often pro-global warming and leave out contending views. For example, the 1990 report dismissed skeptical views scientists working on the report because their views "could not be accommodated."
Basically, global warming may be true, but there is nowhere near the scientific consensus that the UN, Greenpeace and others are claiming. Therefore, before we go crazy trying to do something about it, let's find out if it's true first. There's a lot of work left to be done before you can claim that man-made global warming is a fact.
I am quite aware of the tidal lock issue and was not even taking that in to account. I'm talking about the other compendium of forces that act upon the earth.
I have a hard time taking someone seriously when they consider an unexplained theory as "idiocy". That's pretty much how most of todays most useful inventions and discoveries were initially reffered to as idiocy.
As for how the switch in the Earth's magnetic poles can affect the axis of rotation? Well:
Doesn't the Sun have a magnetic field? How will an Earth field flip interact with the Sun's field, and any flip it may experience during the same period? Has anyone measured the strength and alignment of any magnetic fields that may be present solar-system and perhaps galaxy wide?
Perhaps whatever mechanism shifts the field within Earth's core wil cause a physical torque or change in center-of-mass that causes the axis to change.
If the event lasts 50 years, that might significantly change the weather patterns on the planet. Causing a redistrobution of mass (like polar caps). If the ice-caps shifted 100 miles they might cause the axis to change, or a wobble in the planet's rotation.
The point here is there are a lot of variables. Many of which we can't directly measure. Certainly nobody's instrumented such an event for direct observation yet. And I'm not suggesting that the Earth would suddenly start rotating 90 degrees relative to the Sun. But a change of even one or two degrees of tilt could cause significant change to the system.
And please note that I use "might" and "could" in many places. These are hypothoses and mental musings on my part; ones which I have neither the time, money or equipment to test to any degree. It may be that everything will either cancel out, or the forces involved are so small as to be insignificant on a planetary scale in the timeframe of the event. But I think the questions should still be asked (and answered if possible).
Article X: The powers not delegated... by the Constitution...are reserved...to the people
Though I'm sure I'm not the first to state it, a slowing Earth would increase gravity over time (due to a reduction in the fictional "centrifugal force"), and thus may explain why such huge animals like dinosaurs were at one point abundant, but now extinct. This slowing may just be a natural result of friction from the atmosphere, moon, and fluidic core (ie, compare the spin of a boiled versus raw egg).
Jean Meeus' classic Astronomical Algorithms has some formulae for compensating for this factor. However, they are empirical (i.e. derived from fitting formulae to data as opposed to derived from an established theory), so they have to be updated frequently.
I have a hard time taking someone seriously when they consider an unexplained theory as "idiocy". That's pretty much how most of todays most useful inventions and discoveries were initially reffered to as idiocy.
And I have a hard time taking someone seriously when they pronounce on a subject without researching it first. Or doing the relevant calculations. Suggestions that the earth's rotation axis will suddenly change or shift are appalingly common in pseudoscience, despite zero evidence of them actually happening ever, and no viable mechanism ever being presented.
But I think the questions should still be asked (and answered if possible).
This is the problem; they have been asked and answered. Any torque generated by the interaction of the Earth and Sun's magnetic fields will be felt where the magnetic field is generated (i.e. the liquid outer core); any movement stirred up there will be dissapated by internal friction.
We can already measure past climatic changes as a function of milancovitch cycles; if magnetic polarity reversals had any effect, they would throw a great big spanner into these measurements.
I didn't pronounce anything, I pondered. I didn't say "suddenly" and I never engaged in pseudoscience. Having no evidence for a theory or idea based in scientific pricipals is not pseudoscience, it's pure hypothetical science.
Or do you consider the work on Super String Theory pseudoscience? If not, please provide me with the proof of there being at least ten dimensions.
Pseudoscience is the mis-application of science to further one's own agenda, and usually used in an attempt to prove something that the 'scientist' wants to be true (ghost reports for example).
And have all the questions been asked and answered? Then perhaps you should stop studying geology if we already know everything. All those astronomical physicists should just change their line of work because we have all the answers. Damn, it sure was nice to close the book on all that stuff, what do we solve next?
Fact is we don't KNOW anything about this event. We have hypothesis and expectations that we've piece together from circumsantial evidence. Until the experiment(Earth's magnetic poles swapping) is actually conducted, measured and observed, we have no hard data. Computer modeling has been wrong before and it will be wrong again when new events and unexperienced/measured phenomena are simulated.
Al we can do is sit back, try to prepare and hope for the best, oh... and hope that there's some other method of reliable and accurate navigation for aircraft besides a magnetic compass and GPS.
Article X: The powers not delegated... by the Constitution...are reserved...to the people
Having no evidence for a theory or idea based in scientific pricipals is not pseudoscience, it's pure hypothetical science.
But postulating an idea which is not backed by scientific principals [i.e. the effect of a magnetic pole shift on the earth's rotational axis can be calculated and shown to be trivial], and for which there would be evidence if it actually happened [Geology as a science does really exist, much to the surprise of most of the online community], IS pseudoscience.
Or do you consider the work on Super String Theory pseudoscience?
No, it is a valid field because it is both an extension of existing scientific laws and constrained by observation.
Pseudoscience is the mis-application of science to further one's own agenda, and usually used in an attempt to prove something that the 'scientist' wants to be true (ghost reports for example).
Or a morbid desire for catastrophe.
And have all the questions been asked and answered? Then perhaps you should stop studying geology if we already know everything.
We *know* the laws of physics haven't made any massive changes in the last 10 or so billion years. But there are still some pretty fundamental questions to answer in geology; it's just that the question 'What effect does a magnetic pole flip have' has been asked so many times that it gets boring. And it's quite simple...i.e.
Do pole flips correlate with mass extinctions? NO.
Do pole flips corrleate with true polar wander? NO.
Do pole flips correlate with climatic changes? NO.
Should we expect any major effects (apart from compasses, obviously) from the next pole flip? NO.
So we do know things about this event; it's happened before and it'll happen again.