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Earth's Inner Core Rotation Slower Than Estimated
intellitech writes "Scientists at the University of Cambridge believe they have achieved the first accurate estimate of how much faster Earth's core is rotating compared to the rest of the planet. The rate — about one degree every million years — is much slower than previously thought and arises from the complex dynamic between Earth's inner and outer core, which generates Earth's geomagnetic field. Without our magnetic field, Earth's surface would not be protected from charged particles spewing from the Sun, and life would not be able to exist."
we have to quickly assemble a team to tunnel to the center of the Earth with nuclear bombs to restart the core's rotation!
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
And yet everything is still working. How many other 'estimations', such as distances to distant stars, etc, can be off by a small percentage that would result in a large amount of actual distance? We're human and we do the best we can at estimating.
My inner core rotation is much slower than it should be, especially after a biggish lunch.
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Earth's surface would not be protected from charged particles spewing from the Sun, and life would not be able to exist.
Have gnu, will travel.
Attempts by scientists to measure the earth's rotation at its core failed previously due to motion sickness. However, after desensitizing researchers on The Zipper carnival ride, they were able to reach instruments without puking.
so how far is the date / year off?
This is an estimate, you'll note. But not just any estimate, it's the first accurate estimate.
Were previous estimates wild guesses made just for a laugh, with no expectation of accuracy?
And won't the next estimate researched be able to claim the same milestone, for all the same reasons?
Further studies will show that the core is not only slower than thought, but slowing down quite rapidly. The estimated date for the core to stop spinning at all is December 21, 2012.
SCNR :-)
The Tao of math: The numbers you can count are not the real numbers.
Meh.
We were wrong, and it didn't really affect much of anything.
It bothers me how often I hear absolutes with regards to "If not for XXX, life would not exist on Earth." Life has proven to be a lot more robust than such simple statements imply. Certainly, without a magnetic field, life on Earth would look a lot different than it does today as it would have adapted to a much different environment, but it would most certainly still exist with all other things being equal.
yeah, if some of the standard candles they use to estimate cosmic distances are off by more than a little bit, the error could propagate outwards in a big way. These include things like Cepheid variables and certain types of Supernovae. However if some of your distance scales overlap, it gives some confidence in the numbers and a way to cross-check the estimates.
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...w/o magnetic field. We have oceans which are miles deep. We also have microorganisms which have been found in active volcanoes and inside nuclear reactors. Even humans spend most of the time inside radiation-shielding buildings and have survived trips to moon inside thin metal shell. I think it's more fare to say that life forms would be slightly different without magnetic field.
Don't they know they're changing the rotation speed by measuring it? They're trying to kill us all.
Galactic and intergalactic distances are often estimates.
Even a "known" distance like Sol to Alpha Centari A has a margin of error - 4.365 ± 0.007 ly
Gliese 581, which has been in the news recently is estimated to be 20.3 ± 0.3 ly distant
http://en.wikipedia.org/wiki/Gliese_581
When something is 43,650,000,000,000 kilometers away, does it matter how many hundreds of thousands of kilometers the margin of error is?
that date is off
The particle flux is part of God's creation too. We wouldn't 'tolerate' it, we would rejoice in it as evidence of his bountiful provision of life-affirming radiation for us, his children. For without it we wouldn't be as we would be, and what are the chances of that happening through accidental evolution? Not much!
Why do people keep claiming that if any of the conditions on earth were slightly different, then "life would not be able to exist". Doesn't it make more sense to say that if life did exist, it would be different without a magnetosphere? Life has been shown to be able to exist under some pretty severe conditions.
I've abandoned my search for truth; now I'm just looking for some useful delusions.
You'd hate to run out of gas while traveling that extra 0.3 light years, wouldn't you?
I've abandoned my search for truth; now I'm just looking for some useful delusions.
Another possibility would be to neglect a systematic, distance-dependent effect (either because nobody thought of it, or because the effect is as of yet unknown). For example, say that due to some unknown effect the light intensity decreases slightly faster than 1/r^2. Then we would overestimate the distances of far away galaxies. Since all standard candles would be affected the same way, we would not detect it by comparing the distances calculated with different standard candles.
The Tao of math: The numbers you can count are not the real numbers.
gobak2nursinghome, grandpa
ok. That's all I have to say.
We're all gonna die!
Someday... =)
Chas - The one, the only.
THANK GOD!!!
Since space travel like that is all about the coasting, fuel state wouldn't be a problem.
If you've designed the RTGs to keep the system warm for 20.3ly, the trip being only 20.0 or 20.6 shouldn't really be a mission breaker should it?
When one drives 20.3 miles and the trip actually takes 20.6, does that usually end in running out of fuel?
I've always wondered what god tastes like...
bacon, obviously
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Use the Fuel Rods from the Reactor!
Oceans which would boil at 0 Celsius without an atmosphere.
Yes, but in a car, you can use the brakes to slow down...
Depends. If you're only travelling at thousands of miles per hour (assuming generations of humans living in this imaginary spacecraft) then you may need quite a bit of fuel for course correction towards the "end" of the journey.
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Tapping geothermal energy slowly cools the liquid rock in the outer core. As it solidifies over time, this will eventually have the effect of bringing the rotation rate between the inner/outer core closer together in speed. That, then, could have disasterous consequences for us.
I would expect, however, that the waste-heat exhaust into our atmosphere would cause over-time climate change that would have equally disasterous consequences even sooner. That problem is moot though because the earth is absorbing heat from the sun far faster than it is radiating heat, which will continually cause climate change, and there isn't much we can do about that.
Shouldn't the title be "New Estimation For Earth's Inner Core Rotation Is Slower Than Old Estimation"?
Lets face it, we don't really now how fast it is rotating. We can make estimations and we can revise them, but they are still just estimations. But the title implies that the new estimation is something more concrete than an estimation.
As the imaginary ship gets closer then the margins of error on the distance gets smaller so smaller adjustments are needed.
They build in course corrections into long space flights like this for a reason.
If you read up on the history of space probes within our Solar System, you'll see course corrections built into the mission for just this purpose.
http://www.qrg.northwestern.edu/projects/vss/docs/navigation/1-what-is-course-correction.html
Okay, I understand it is important to note why some specific area of research (Earth's core speed) is important research (relates to magnetosphere, amongst other things). But can we please leave out stupid addenda to summaries like, "Without our magnetic field...life would not be able to exist." The interesting news story here relates to geology, geophysics, and planetary models (something becoming more and more relevant as we explore further portions of our solar system). I would much rather see a discussion relating to those topics, than see a number of completely off-topic threads about whether or not life would or would not exist without the magnetosphere. Yes, that's an interesting question, but the existence of life has little to do with this research. And, as such, establishing a connection between the existence of life and the geophysical model of the Earth in the summary is little more than mild flamebait (off-topic-bait?).
What I am curious about is what, specifically, this type of research can do for our understanding of the magnetic poles traveling, our understanding of climate models, our understanding of other planetary bodies which we suspect might have a liquid core. Considering that life exists now (with the core being slower than we thought) and life existed within earlier models (when the core speed was suspected to be higher) I don't think these findings have much, if anything, to do with the potential for the existence of life. So can we please try to keep discussions on topic?
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And in space you can use a planet or star's gravity to slow down.
I will stop the inner core rotation with my doomsday device.
Unless I am paid one million dollars.
Oh wait, how do I leave the planet.
Dr. Evil.
Deinococcus radiodurans takes your puny solar radiation, chews on it, and spits it out as not worthy of food. Go ahead, try and kill me!
http://en.wikipedia.org/wiki/Deinococcus_radiodurans
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
The earth is also shielded by solar wind interacting with the ionosphere. As the geomagnetic field has gone to zero during reversals and primates of 780 thousand years ago survived just fine, maybe we should just file this business of "no protection without magnetic field" under "more nonsense oft taught in schools that is rubbish".
And that's one of the beautiful and valuable things about science - that it is able to quantify and bound the error in its measurements / predictions / certainty. Small minded pundits, especially when they want to attack a conclusion produced by science, go on and on about how science can never be certain about anything: it's all just a theory. As though a theory has no value because it has some uncertainty in it! Or because every detail of every intermediate step isn't perfectly quantified. Just because I can't say that Alpha Centauri is exactly 4.365 ly away isn't the same as saying I don't know how far away it is: I can say, with certainty, that it is more than 4.358 ly away and less than 4.372 ly. Even if it is not exact, it's still pretty damn useful and insightful.
It was predicted by computer modeling the core dynamo by a Harvard group in the 1990s. At that time is was the frontier of supercomputing because you had to make the model cells rather small to accurately coupled elastic-electrodynamic equations. Ad a seismology group at Columbia claimed it saw super-rotation in 30 years of seismic records. Velocity anomalies (anisotropy) in the earths core appeared to have moved during just a few decades. Both these studies suggested the Earth's core had an "extra day" about every millennium. This new study suggests a slower degree of super-rotation from another kind of seismic measurement- bumps on the surface of the earth's core.
Thus creating an atmosphere, clouding up, and cooling them down again.
Could take some time before the whole run-out-of-water thing happens. Time enough to start up the magnetosphere again.
It would just get carried off into space by the solar wind. See: Mars.
I can say, with certainty, that it is more than 4.358 ly away and less than 4.372 ly.
Well, maybe.
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Without our magnetic field, Earth's surface would not be protected from charged particles spewing from the Sun, and life would not be able to exist.
http://www.spiegel.de/wissenschaft/weltall/0,1518,300232,00.html
It's in german, but it says: "no, the solar wind would generate a magnetic field almost as strong as earth's one"
Your certainty here is 3, 4 or 5 standard deviations?
Ok, i just wanted to nitpick
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Most scientific estimates are significantly more accurate than the roadsigns telling me how many miles it is to the next few cities. Nevertheless, those signs have never caused me any problems and I'd rather have them than not. Usually, exceptional precision is unnecessary.
"Convictions are more dangerous enemies of truth than lies."
See Venus. Tell us how it really keeps its atmosphere.
And in space you can use a planet or star's gravity to slow down.
But I gotta make #2 now...
Just like Mars, Venus's atmosphere is 96% Carbon Dioxide, which is heavy enough not to get blown off into space by solar wind.
What if we use an inverse tachyon beam to channel the solar wind directly into the Earth's core? That might give it enough extra power to kick up the rotation speed and strengthen the magnetic field. We'll have to use one of the Moon's craters as a deflector dish to create a containment beam around the tachyon particles so the solar wind doesn't leak but I think I can make it work.
...How many other 'estimations', such as distances to distant stars, etc, can be off by a small percentage that would result in a large amount of actual distance?
Umm, I'll estimate 30%... it would be larger but sales and marketing departments have not yet become involved in things like interstellar distance and core super-rotation.
You have the right to remain sentient. If you give up the right to remain sentient, you will be elected to public office
"It is shown by kinematic estimates and three-dimensional plasma-neutral gas simulations that the solar wind can induce very fast a magnetic field in the previously completely unmagnetized Earth's ionosphere that is strong enough to protect Earth from cosmic radiations comparable to the case of an intact magnetic dynamo.
Consequently, even in the case of a complete breakdown of the Earth’s dynamo, the biosphere is still shielded against cosmic rays, in particular coming from the sun, by the magnetic field induced by the solar wind. "
Fandroids hate facts.
I'm a layman but I would expect that, after 4.5 billion years, friction would have slowed down the inner core's rotation to match that of the rest of the planet. Has anyone hypothesized why that hasn't happened?
Since all standard candles would be affected the same way, we would not detect it by comparing the distances calculated with different standard candles.
Until you cross calculate non-luminosity figures and it means galaxies must move faster than the speed of light, or rotate too quickly for their apparent density, or the redshifts indicate something weird, or typical stellar evolution would imply that distant galaxy should have collapsed into a black hole already, and measured supernova luminosities would not be remotely close to theoretical, etc.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
So, the core rotates 1degree faster than the surface every million years. That's not much.
At the current rate of earth's rotation rate slowing, the surface will slow down some 30 degress in the next 400 years (this is a reasonably sound estimate used by people arguing against continuing "leap-seconds", that as the rotation rate slows geometrically, soon we'll be adding a leap second every month, then several a month, and so on. They suggest a leap-hour in 300 or 400 years.)
So...this suggests that the solid core and the solid crust are linked together very closely, so that the core tracks the crust almost perfectly. I find this somewhat hard to believe, given that there is a few hundred miles of not-very-viscous liquid iron/nickel between the inner core and the plastic mantle...
I love Mondays. On a Monday, anything is possible.
specifically, an induced magnetosphere:
http://en.wikipedia.org/wiki/Atmosphere_of_Venus#Induced_magnetosphere
but it is very weak, so the solar wind penetrates deeply, into the exosphere, meaning venus is losing its hydrogen and oxygen
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
What the hell is an "accurate estimate"?
Since space travel like that is all about the coasting, fuel state wouldn't be a problem.
Coasting is a big part of space travel (one of Newton's laws says an object in motion will stay in motion until another force acts upon it), but is it really possible to plan out a perfect space journey without need for fuel-assisted adjustments? Of course not. You can run out of gas in space.
They'd also freeze like numerous bodies in our solar system, Europa being the best known example.
https://en.wikipedia.org/wiki/Inverted_totalitarianism
If it slows down too much, we'll be forced to fix it with that old Sci-Fi catch-all procedure; "NUKE IT!"
Who said anything about no atmosphere?
"When one drives 20.3 miles and the trip actually takes 20.6, does that usually end in running out of fuel?"
Tell that to 1991's Ayrton Senna.
See: way stronger gravity than Mars to keep gases anchored down.
It might not matter from a technical point of view, but all the "are we there yet?" questions could really drive you mad.
Whenever in an argument, remember this.
There aren't that many De Loreans still available
It is the fault of those right wing tea baggers. They're doing this to create global warming so Al Gore can make more profits on his Carbon Credit schemes. Bet you didn't know that Albert was a secret controller for the Tea Party! It's true. You read it here!