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Japan Earthquake May Have Shifted Earth's Axis
Zothecula writes "Using a complex model to perform a theoretical calculation based on a US Geological Survey, Richard Gross of NASA's Jet Propulsion Laboratory has determined that by changing the distribution of the Earth's mass, the earthquake that devastated Japan last Friday should have sped up the Earth's rotation, resulting in a day that is about 1.8 microseconds (1.8 millionths of a second) shorter."
... the work day got about 0.6 microseconds shorter, woo! Oh, wait....
Now I need to recalibrate my clocks!
I've abandoned my search for truth; now I'm just looking for some useful delusions.
We had the same story about a year ago: http://science.slashdot.org/story/10/03/02/0114236/Chilean-Earthquake-Shortened-Earths-Day
Did I read that correctly? Did the summary explain to us what a microsecond is?
May have? Every time you move an apple from one side of the room to the other it'll shift the axis. Something like this has done it for sure. The only question is: how much? This is a perfect example of journalists needing to have two viewpoints and just not understanding which are the possible differences. Anybody who thinks there are two (rather than one or many) possible right answers is in need of either and anti-lobotomy or a brain transplant....
=~ s,(.*),<sarcasm>$1</sarcasm>,g if any_point_you_wish();
Because it's been a long winter and I'm ready for warmer weather.
Shift happens.
Everytime I heard that the Earth's axis had been changed during the Chile earthquake, I figured it was the rotation axis. I thought it was a little far-fetched, but I wasn't one to argue with the data. However, it is NOT the rotational axis that was shifted and this article finally clarifies that. I read many others before (probably regurgitations of the real scientific paper) and they never said that.
Apparently, the axis that shifted is that of mass, called the Figure Axis, meaning the axis of symmetry in the Earth's mass distribution. We're still rotating in the same direction (defined by an axis which is not the Figure one), though.
Eh, it's just God setting us up for 2012. Just needed to tweek the axis a bit before he could start destroying us all. It's like tuning a set of rabbit ears on an old television.
1.8 microseconds....give or take a second
Tee Three Gorges Dam.
http://www.theenergywatch.com/2010/06/18/three-gorges-dam-and-the-earths-rotation/
Bam.
A bunch more like this, and we can get rid of the leap year..
For justice, we must go to Don Corleone
Now i will live more miliseconds.
not too smart this one, kinda like what's heavier a pound of feathers or a pound of bricks.
Comment removed based on user account deletion
Each time a meteorite hits the moon, it shifts it slightly which might likely have a bigger impact on earth than human activity does (affecting tides and waves). Also dinosaurs were MUCH bigger that humans. Defecating Brachiosaurus were likely the first cause of global warming (being endotherms).
Views expressed do not necessarily reflect those of the author.
Many of the comments on here are "1.8 microseconds, oh no I get less sleep! What a stupid finding."
But seriously, does this have an effect on GPS? GPS satellites need to be corrected for relativistic effects that cause their clocks to tick 38 microseconds/day different than the ground; which would cause error to accumulate at 10km/day. Does 1.8 microsecond difference in our day cause error to accumulate in GPS at the rate of 0.5km/day if not fixed?
I wonder if anyone has taken into account this change in the length of the day on GPS position data. It seems on the face of it, that the GPS satellites that are in geo-synchronous orbit would need to have their orbits adjusted to compensate. Otherwise, position data will slowly drift. Anyone have any information (or expertise) regarding this?
That's not 'sleeping', that's 'dead'.
Lost at C:>. Found at C.
We need to fund research on how we can use this mechanism to create the 25hr day so I can get an extra hour (preferably for sleep) each day.
Newton still right!
Basic principles of mechanics remain sound!
Film at eleven.
The speed of the Earth's rotation changes every time I ride an elevator, too. (Please resist the temptation to make a fat joke here; it's too obvious to be worth the trouble.) On a more impressive scale, there's a significant and variable amount of angular momentum stored in the atmosphere. Changes in major air currents year over year (things like El Nino, for instance) can change the length of the day by close to a millisecond: hundreds of times more than this little earthquake.
~Idarubicin
The older I get and the more I learn, the more I appreciate straightforward explanations of things in laymans terms.
My noggin only has so much storage. Having to remember the academically approved (sometimes obscure) technical terms for every phenomena in physics is a burden.
Just the start of 12/21/2012....DUN DUN DUN
How did an earthquake change the mass of the earth? I didn't think it was strong enough to eject debris in to space.
Changing the density, shape, or distribution of mass of the earth I can understand, but as far as I know all the mass is still here.
It really depends on who you are buying your bricks and feathers from. I would suggest buying either in bulk. You will get a lot more for your money.
If you live on a mostly island nation, there is nowhere to run , nowhere to hide
Personally, as an atheist, i'm tempted to pray for my (potentially future) friends over there
Different cultures, they don't matter...
Even now in the 21st century on earth we can have our "chestnuts" rattled quite easily
5.2,5.3 richter here in athens feels like nothing at all to worry about....
and btw, don't forget our new zealand friends who are facing even more aftershocks...
Andy
I really doubt that any recent human activity really plays a significant part in the scale of the Earth's rotation/axis. The earthquake released an equivalent energy of ~300mt of TNT. That's the equivalent of thousands of nuclear weapons being exploded.
On the grand scale of things, we don't play that big of an impact on a geological scale. Mother nature is a lot more awesome than anything we could come up with.
Also, what if someone wanted to deliberately slow down the earth's rotation? Say, by turning a motor against it?
I did a quick back-of-the-envelope calculation that suggests someone could slow down the earth's rotation by 5% by spending $30 billion on electricity to turn a motor in the appropriate direction.
Information theory is life. The rest is just the KL divergence.
Now i will live more miliseconds.
How is this a troll?
Because the Earth is rotating faster, we all just sped up a bit. You'll still live the same # of vibrations of a cesium atom on Earth, but to an outside observer, our cesium atoms are doin their thang a tad slower than theirs, and we will live a bit longer, relatively.
"I really doubt that ..."
You would be wrong: http://findarticles.com/p/articles/mi_m1200/is_n7_v149/ai_18051356/
That's not 'sleeping', that's 'dead'.
You mean Vinnie is actually going to send me sleep with the fishies?
A pound of feathers may weigh as much as a pound of bricks, but an ounce of gold weighs more than an ounce of feathers, and a pound of gold weighs less than a pound of feathers.
When our name is on the back of your car, we're behind you all the way!
All mechanical engineering students know you can accomplish that with a 1HP motor. Finding the gears might be somewhat more of a challenge though, maybe we could use the moon as a gear.
Custom electronics and digital signage for your business: www.evcircuits.com
Yay, with this 'newfound' knowledge all we need to do is build some space elevators, push enough mass far enough out to slow the earths rotation to be evenly divided by it's rotation around the sun, and we can get rid of all the crazy leap day rules. Make computer time actually doable in a real way.
I know people in my high school that never took a physics class. That was almost 20 years ago. I think it's probably worse now.
This is not something to be proud of.
Dan
Well, if you climb a mountain, or move towards the equator, you will slow down the earth's rotation.
This in turn reduces the centrifugal force, and makes everybody slightly heavier.
Lawsuits will follow.
can we get rid of daylight savings time!??
http://www.standardtime.com/
I've had a perfectly wonderful evening. But this wasn't it. -- Groucho Marx
Only problem is Chao is wrong about the direction of the impact. Raising water increases the mass moment of inertia slowing the earth's rotation except at very high latitudes. He did not do a rigorous analysis. Melting icecaps would also slow rotation.
The US government have made it clear that we have no inalienable rights; any we do not defend vigorously will be taken.
Gyroscopes would be far more effective.
The US government have made it clear that we have no inalienable rights; any we do not defend vigorously will be taken.
Look at the amount that the pole moves and the length of day changes annually. The normal variations are 1000 times greater than anything the earthquake has caused. See the IERS saying "hardly discernible" because a large snowstorm can cause a greater change.
The largest hydroelectric power plant reservoir in the world is actually a natural lake, lake Victoria in Uganda. This lake serves the reservoir for the Nalubaale (formerly Owens Falls) dam.
The large total volume of water and the fact that it's located at the equator makes it the reservoir with most influence on the earth's rotation rate.
1.8 microseconds (1.8 millionths of a second)
Second? I don't care for a second, the second is the first loser!
What I want to know is who is on first.
Well, I guess he could be wrong, or you could be wrong?
Indeed, it's a very small shift, but looking at the past 30 odd years and the calamities and "jitters" earth has faced, don't you think it's adding up to something significant? I really believe that the number of natural disasters will increase in the future, since we have royally screwed up things under the sea (oil), above the clouds (ozone) and everything in between.
We just have everyone do this: http://xkcd.com/162/
A pound of bricks is heavier.... Try dropping it on your toes :-P
Just because water rose up due to a plate under it rising doesn't mean something else that was heavier didn't go under that plate. That would decrease the moment of inertia. After all, this was due to a plate sliding under another plate.. (Not saying that is just what happened, but there may be other factors.)
This is the second KNOWN possible shift. The first was the one off of Indonesia that was a 9.1 (about). So I wonder, does this mean that a quake of magnitude over 9 will cause a shift in the earths rotation. I wonder if the meteor that hit the earth that 'killed the dinosaurs' caused such a shift or larger which resulted in the climate change that changed this world forever.
Only 'flamers' flame!
It doesn't help that there are about six completly different measuresments call the 'ton' or 'tonne.' The metric system was introduced to replace the terrible mess of often contradictory units that were in use before - and remain in use in the UK, and just about nowhere else.
We do use imperial in the UK for a few things - speed limits, beer - but most measurements are metric now.
As the article explains, the water is moved closer to the earth's axis despite being at a higher altitude. The north pole, for instance, is zero distance from the axis.
This is due to the majority of reservoirs being further away from the equator than the majority of the water sources and thus water is being moved closer to the axis.
Melting land-based ice caps certainly would slow rotation, but this is because they are at the poles, not because they are higher up.
Now my iPod *really* won't wake me up in time!
It doesn't help that there are about six completly different measuresments call the 'ton' or 'tonne.' The metric system was introduced to replace the terrible mess of often contradictory units that were in use before - and remain in use in the UK, and just about nowhere else.
We do use imperial in the UK for a few things - speed limits, beer - but most measurements are metric now.
Fortunately the US has adopted a simpler, more consistent set of measurements. For example, my car gets 40 rods to the hogshead, and that's the way I likes it!
"All these years believing you're the signified monkey, only to find out you're just a big hunk of nobody cares."
Remain in use in the US, rather. One letter, so much change in meaning.
But nothing to attach the motor too. Maybe you could use a series of railguns on the equator, shooting mass at a shallow angle and above escape velocity like a catherine wheel firework? Or change the orbital velocity through an interaction with the sun's magnetic field? Or you could try moving an ocean around just a little bit ahead of the tide, thus speeding up the moon's orbit at the expense of the earth's rotational velocity.
Yep, earthquakes always do this. It's only the really big ones that affect it enough for us to bother talking about, though.
I didn't mean the rotor would press against the earth (like a moving gear). If you just attached it to a frame and had electricity flow in to power it, then the alternating magnet on the stator would apply a moment on the magnet, and a moment in the opposite direction on the frame. As long as the frame doesn't rotate relative to the ground, there is another opposite moment at its interface with the earth's surface.
Or did I just really doze off in my reasoning there?
Information theory is life. The rest is just the KL divergence.
Nope, that's a euphemism.
Which, in this case "That's not 'sleeping', that's 'dead'." still applies. :-P
Lost at C:>. Found at C.
Simple equal and opposing forces.
Now, on the other hand, if you lay down on the floor from a standing position, you have had an impact on speeding up the rotation of the Earth.
Ultimately the net effect of all of us moving ourselves (and apples) around all day has little cumulative effect. However, if you engage in the fun activity of burning petrol in your automobile, which was once deep in the ground, you have actually contributed to change in the Earth's rotation. Also, if you climb a hill, pick up a hand full of rocks and move then down the hill, you have also had an effect. I'd go so far as to say the erosion of mountains, if not offset by new mountains rising up, is having a rather large effect and has been going on for quite a long time.
This fits neatly into my theory that the Earth once spun slower and has since sped up, thus casting the last living dinosaurs into space.
A feeling of having made the same mistake before: Deja Foobar
He's not dead, he's just pining for the Chryslers.
rewriting history since 2109
Just askin'.
I live in sweden, I don't have to care about stuff like that.
1. Lake Kariba (180 km3 or 43 cu mi; Zimbabwe, Zambia)
2. Bratsk Reservoir (169 km3 or 41 cu mi; Russia)
3. Lake Nasser (157 km3 or 38 cu mi; Egypt, Sudan)
4. Lake Volta (148 km3 or 36 cu mi; Ghana)
5. Manicouagan Reservoir (142 km3 or 34 cu mi; Canada)
6. Lake Guri (135 km3 or 32 cu mi; Venezuela)
7. Williston Lake (74 km3 or 18 cu mi; Canada)
8. Krasnoyarsk Reservoir (73 km3 or 18 cu mi; Russia)
9. Zeya Reservoir (68 km3 or 16 cu mi; Russia) Read more: http://wiki.answers.com/Q/What_is_the_largest_man_made_lake_in_the_world#ixzz1GnVTwRD4
The US government have made it clear that we have no inalienable rights; any we do not defend vigorously will be taken.
I remember this same thing happening with the indian quake not long ago. Shift Happens.
Consistent my eye. There are two different lengths called rods (survey and international) and a hogshead varies by the type of liquid, even varying by the variety of the type. For example, a hogshead of ale is 665.44L and a hogshead of beer is 748.62L. For wine, a hogshead of claret is 209L; port, 259L; sherry, 245L; and Madeira, 209L. So, is that 40 survey rods to the premium gasoline hogshead or 40 international rods to the regular gasoline hogshead?
When our name is on the back of your car, we're behind you all the way!
The length of the day already slows by about 15 microseconds per year due to tidal friction. To equal that effect, we'd need about 8 quakes of this size every year.
Only because it's already considering "full time work" actually managing through the damn winter in Sweden ;)
"The radius of the planet shrinks"
But wouldn't it grow back to the original size since there's land being created... like in Hawaii or by some volcano? Therefore the speed should return back to normal.
Change is normal I say.
If I say I don't know are you going to throw me off a bridge?
"All these years believing you're the signified monkey, only to find out you're just a big hunk of nobody cares."
If I say I don't know are you going to throw me off a bridge?
That depends on if Schrodinger's cat likes you or not... God help you if something would happen to that cat before the trial...
Could you please express that in terms of Libraries of Congress ?
Wet or Dry?
Thanks for letting me vent.
The subject who is truly loyal to the Chief Magistrate will neither advise nor submit to arbitrary measures (Junius)
Well, if you climb a mountain, or move towards the equator, you will slow down the earth's rotation.
This in turn reduces the centrifugal force, and makes everybody slightly heavier.
Lawsuits will follow.
So wait, what you're saying is we have to slashdot a mountain now?
"If I say I don't know are you going to throw me off a bridge?"
I'll try. Then, if you manage to stay afloat that will mean you are made of wood, therefore you are a witch.
"Wet or Dry?
Weeeeeeeaaahhhh!
It's just easier to keep a recording of them on your iPhone, ready to play at the push of a button. Like my friend does whenever I tell a joke.
"You saved 1968." - Ms. Valerie Pringle to the crew of Apollo 8
No, seriously. I did.
Any movement of mass on (or in) the Earth results in a change in the moment of inertia, and therefore in the location of the Earth's rotation axis and rotation rate.
This is not news, and hasn't been for decades. I recall in the 1970s seeing work that demonstrated a shift of the rotation pole consequent on (IIRC) the 1964 Alaska earthquake.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"