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NASA Details Earthquake Effects on the Earth 309

Posted by CmdrTaco from the measuring-stuff dept.
Cuyamaca writes " NASA scientists, using data from the Indonesian earthquake calculated it affected Earth's rotation, decreased the length of day, slightly changed the planet's shape, and shifted the North Pole by centimeters. The earthquake that created the huge tsunami also changed the Earth's rotation." You now have 2.68 fewer microseconds each day to do whatever it is you do.
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NASA Details Earthquake Effects on the Earth More

NASA Details Earthquake Effects on the Earth

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  • 2.68 micro seconds missing... (Score:5, Funny)

    by beh ( 4759 ) * on Tuesday January 11, 2005 @11:02AM (#11321245)

    Let me guess, those are missing in the night, right?

    At least that would explain my lack of sleep lately... ;-)

  • So that's why my watch is running slow. (Score:5, Interesting)

    by IO ERROR ( 128968 ) * <error.ioerror@us> on Tuesday January 11, 2005 @11:02AM (#11321251) Homepage Journal
    The researchers concluded the Sumatra earthquake caused a length of day change too small to detect, but it can be calculated. It also caused an oblateness change barely detectable, and a pole shift large enough to be possibly identified. They hope to detect the length of day signal and pole shift when Earth rotation data from ground based and space-borne position sensors are reviewed.

    Too small to detect? Then why is my watch running slow?

    Seriously, this means we'll need an additional leap second once every thousand years or so. Unless, of course, something else changes the length of the day, which will likely happen first.

  • Yikes. (Score:2, Funny)

    by grub ( 11606 )

    Bartender, another Fort Garry Dark [fortgarry.com], and hurry!

  • CRAP! (Score:5, Funny)

    by dynamo_mikey ( 218256 ) on Tuesday January 11, 2005 @11:05AM (#11321286)
    You now have 2.68 fewer microseconds each day to do whatever it is you do.

    Damn! My project is already behind schedule, this is the last thing I need. Oh well, better stop reading so much slashdot ;)

    -dynamo

    • Re:CRAP! (Score:3, Insightful)

      by Zutroy Of Earth ( 114413 )
      On the other hand, this means that we'll all technically live longer!
      I've probably gained about .07 seconds of life. I wonder what I'll do with it ...
    • Oh well, better stop reading so much slashdot ;)

      You should read more slashdot, since if this keeps happening, you'll have less and less time per day in the future to read it. :)
  • Ack - there's already not enough time in my day, and now it's shorter!

  • I 3 Brad (Score:5, Funny)

    by frogger01 ( 806562 ) on Tuesday January 11, 2005 @11:05AM (#11321294) Journal
    You now have 2.68 fewer microseconds each day to do whatever it is you do.

    great, more time for people to do things like this [funpic.hu]

  • Great! (Score:3, Funny)

    by myusername ( 597009 ) on Tuesday January 11, 2005 @11:05AM (#11321296)
    Now how am I supposed to find the time to get all those TPS reports done!
  • Will the changes in Earth's rotation affect it as well?

    • Re:What about the moon? (Score:5, Informative)

      by centauri ( 217890 ) on Tuesday January 11, 2005 @11:41AM (#11321767) Homepage
      Good question. Right now, the moon is receiving a boost to its orbital velocity every (Earth) day, due to irregularities in the shape of the Earth. This moves the moon farther away and slows down the earth's rotation. Conservation of angular momentum, doncha know? The earth has sped up, in this case. It has gained angular momentum. Since it's rotating more rapidly now, I'd say that the moon receives its boost more often and will move away more quickly. In the (very) long term, and barring further changes, the moon will end up moving farther away, because the earth now has more angular momentum to lose.

  • Oh well... (Score:5, Funny)

    by pastpolls ( 585509 ) on Tuesday January 11, 2005 @11:07AM (#11321309)
    You now have 2.68 fewer microseconds each day to do whatever it is you do.

    Well, there goes my sex life.

  • changes in rotation (Score:4, Funny)

    by Pompatus ( 642396 ) on Tuesday January 11, 2005 @11:07AM (#11321311) Journal
    calculated it affected Earth's rotation, decreased the length of day

    Does this mean that NASA confirms that superman can indeed turn back time?

  • bonus! (Score:5, Funny)

    by theMerovingian ( 722983 ) on Tuesday January 11, 2005 @11:07AM (#11321317) Journal

    You now have 2.68 fewer microseconds each day to do whatever it is you do.

    Yay! My first raise in pay since 2001!!

    • It's not a pay raise since it comes out of your free time (fleep, time with family, etc). This is clearly unfair, thus I demand the work week be shortened to 39:59:59.999986.6!

  • Atomic clocks? (Score:3, Insightful)

    by SethS ( 721867 ) on Tuesday January 11, 2005 @11:07AM (#11321320) Journal
    Is this change big enough to update the atomic clocks? I think this quake really puts things into perspective - the Earth (and "24 hours in a day") isn't as set in stone as people think it is. (Pun intended?) And who knew the poles could move?
    • The movement of the magnetic poles has been known for many years. They used to be much further South a few million years ago. There is only one physical pole, The South, the North Pole is water (which just happens to be frozen). The physical poles are defined by latitude and longitude measurements which the earthquake didn't change enough to matter.
    • the second is based on the speed of light, which obviously did not change due to the earthquake.

      this will necessitate addition of leap second, so the "day" calculated via the defined "second" will correspond to the one rotation of the earth.

      • Re:Atomic clocks? (Score:3, Informative)

        by Martin Blank ( 154261 )
        An SI second is "[t]he interval of time taken to complete 9,192,631,770 oscillations of the cesium 133 atom exposed to a suitable excitation."

        Light is used to measure the meter, which is the distance that light in a vacuum travels in 1/299,792,458 of a second. (I seem to recall that a particular wavelength is used for that, but I can't find it now.)

  • Erm Editors? (Score:5, Insightful)

    by OverlordQ ( 264228 ) on Tuesday January 11, 2005 @11:07AM (#11321321) Journal
    NASA scientists, using data from the Indonesian earthquake calculated it affected Earth's rotation, decreased the length of day, slightly changed the planet's shape, and shifted the North Pole by centimeters. The earthquake that created the huge tsunami also changed the Earth's rotation.

    What exactly do you editors do besides add pointless side comments? Evidently not editing.
    • The editors didn't add that comment, that comment was added by the submitter (Cuyamava) of the article. The editor added whatever was outside the quotes.
  • Wow, the Tsunami increased my life expectancy by 50,713.6 microseconds.
  • Damn, no wonder I'm feeling so tired lately

  • Changed and Affected (Score:5, Insightful)

    by kryzx ( 178628 ) * on Tuesday January 11, 2005 @11:10AM (#11321346) Homepage Journal
    So it "affected Earth's rotation" and "changed the Earth's rotation"? Wow. Can't blame the poster, I guess, since that was a direct quote from the article.

    I like this quote, which underscores the lack of newsworthiness of this, "Any worldly event that involves the movement of mass affects the Earth's rotation, from seasonal weather down to driving a car." So, using that fancy scientific notation to represent all the zeroes between my numbers and the decimal point, I can compute the change in rotation and pole location caused by my commute this morning. Call the newspapers!!!

    • > "Any worldly event that involves the movement of mass affects the Earth's rotation, from seasonal weather down to driving a car."

      I'll be driving to work this morning, unless the governments of the world pay me...one million dollars. (In which case I'll sit around and watch Spongebob.)
    • > So, using that fancy scientific notation to represent all the zeroes between my numbers and the decimal point, I can compute the change in rotation and pole location caused by my commute this morning. Call the newspapers!!!

      there's nothing "fancy" about the scientific notation... you will not be able to compute the changes in the rotation and pole locations due to your daily commute no matter how many zeros you tack on unless you idealize (i.e. assume everything else to be constant) the problem. ther

      • I disagree. I know the mass of my car and its location and elevation at home and at work with good accuracy. I also know the mass of the earth. That's all I need to calculate the change in rotation.

        "...there's too much noise in the data/measurements to reliably attribute such changes to your daily commute."
        Hey, no one said any thing about attributing measureable changes to anything. And that is exactly my point. No one in the article is explaining measured changes. They just did calculations and g

  • Earth-rearranging earthquakes commonplace (Score:5, Insightful)

    by saddino ( 183491 ) on Tuesday January 11, 2005 @11:12AM (#11321366)
    A CNN article [cnn.com] on this subject included what I thought was a fascinating quote:

    In human time, earthquakes that powerful are rare, but in the vastness of geologic time, they are commonplace. "An earthquake of this magnitude, in this part of the world, has probably occurred about a million times since the breakup of Pangea," said Chris Scotese, a geophysicist at the University of Texas-Arlington. "No exaggeration."

    Too often we're bounded by thinking of events in human time scales (if not generational time scales) but a 9.0 quake is just a regular occurance in the life of the Earth. It's suppose it's events like these that reveals how insignificant we are in the grand scheme of things.
    • "It's suppose it's events like these that reveals how insignificant we are in the grand scheme of things."

      And I know it's not a popular sentiment, but it aslo puts man's capability to affect the Earth into perspective. More energy was released by this quake than mankind is capable of producing, yet we are supposed to believe that we can significantly alter the Earth's climate in a mere 130 years?

      • the quake released more energy than people are producing... in a year, not ever.
        And energy isnt everything. Little influences in the right points can lead to huge results. Especially because the athmosphere is TINY compared to the mass of the earth, and our climate depents totally on it.
        Compare venus, earth and mars to see what 1/100000 of a planets mass can do, and this tiny part is much easier to change than the large body the quake is affecting.
    • It may also reveal how insignificant the grand scheme of things is in our individual lives. A large earthquake like this may be common in "the vastness of geologic time", but given that I'm here for such a short period of that, the "vastness of geologic time" doesn't seem to really pertain to me too much. We may have an earthquake like that tomorrow, but it's unlikely. Either way, not much I can do about it.

      To me, it seems MOST appropriate to think of events in "human time scales", since that scale is m

    • Heres an idea thats been floating around in my head for the last while... how much of an earthquake, raised landmass or change would you need to move the poles significantly? Not that I'm planning any Doctor Evil maneuvers, but thinking back on global flood legends, in many cultures, how much would it take to roll antartica north enough to melt the kilometers high ice on it? Or vice-versa, before it was that far south?

      The Atlantis myth could have been a case of a mega-quake (or series of powerful quakes a

      • how much of an earthquake, raised landmass or change would you need to move the poles significantly?

        I learned in my geology class that the magnetic poles have switched polarity often on the geologic timescale.

        In the middle of the Atlantic ocean is a large trough running north/south where two tectonic plates are separating (this is the mechanism that caused the breakup of the supercontinent Pangea). When lava cools, the earth's magnetic field is "recorded" in the rock. Geologists have discovered magneti
      • ...how much would it take to roll antartica north enough to melt the kilometers high ice on it?

        I'd guess that it would take an earthquake so large that melting ice wouldn't be our primary concern. Really, how many miles north would Antarctica have to move for there to be significant melting? 100 miles? 200? 500? If a 9.0 quake only moved the North Pole a few centimeters, we're talking a pretty huge quake to move a whole continent hundreds of miles.

        • Yeah but take a football on a field... flawed analogy on many levels, I know, but bear with me. If you give it a kick, it rolls. A giant mega-quake would be a kick. If you push it with a finger lightly, it moves slightly then rolls back. If you push it two or three times lightly however, before it had a chance to reassume its original position, it would roll enough to settle in its new position, such as a series of powerful quakes would effect.

          Besides we know very little about the internal structure of the

    • Too often we're bounded by thinking of events in human time scales ...

      Very true. It's the main problem in the evolution-creation debate. When creationists are not simply asserting the ultimate authority of scripture, they're insisting that living things are simply too complex to have been created by a series of random events. That argument only makes sense if you fail to consider just how huge the history of this planet is.

      But then, who can? I can accept that the earth is billions of years old in a det

  • Pangea (Score:5, Interesting)

    by sameerdesai ( 654894 ) on Tuesday January 11, 2005 @11:15AM (#11321396)
    I read on CNN science page [cnn.com] that scientists normally look for big events like these (quakes measuring more than 9) in order to learn more about earthquakes. However it was extremely difficult to learn anything as most of the fault lines are deeply buried in ocean bed. Other theory is that these kind of pheneomenon was what resulted in formation of all the continents as we see today from a big land mass lump called Pangea which existed millions of years ago. Another theory is now that these continents are on move again getting closer to forming a big lump. Australia is on a collision course with Asia and North America with Europe. Africa is pushing up on Europse and reducing the Mediterranean region. Considering the technological knowledge this is really neat however considering human lives this is very very sad incident.

  • Oddly enough (Score:5, Funny)

    by revery ( 456516 ) <`charles' `at' `cac2.net'> on Tuesday January 11, 2005 @11:16AM (#11321416) Homepage
    You now have 2.68 fewer microseconds each day to do whatever it is you do

    Oddly enough, this is the exact length of a 30 minute sitcom minus commercials... I wonder which show this will force off the air?

    --
    Was it the sheep climbing onto the altar, or the cattle lowing to be slain,
    or the Son of God hanging dead and bloodied on a cross that told me this was a world condemned, but loved and bought with blood.
    • Oddly enough, this is the exact length of a 30 minute sitcom minus commercials...

      You forgot a term: 2.68 usec = 30 minute sitcom minus commercials, minus the stupid bits.

      --Rob

  • No to Worry (Score:5, Informative)

    by dutky ( 20510 ) on Tuesday January 11, 2005 @11:17AM (#11321431) Homepage Journal
    While the day may have gotten shorter, the orbital period of the Earth didn't change, so you get the time back over the entire millennium as an extra leap-second [navy.mil].
  • . . the grass was greener, kids were polite to their elders and the day was longer!
  • Someone please help me out here. If we lost time in our day, that would mean the Earth is spinning faster. I thought that the faster an object moves, the slower time goes. So wouldn't this sort of cancel everything out in the long run?
    • time dilation effect is completely negligible unless you get to appreciable fraction of the speed of light. earth's rotation is nowhere near that.

      "the strong force is much stronger than the gravitational force" - but you cannot take such a statement without understand their relevant domain. without understanding the relevance, "then why aren't we feeling this strong force instead of the gravity?" sounds silly. same thing here - you cannot take "faster the object moves, the slower the time" without underst

    • Let's look at that... The earth has a circumference (at the equator) of 24,901.55 miles [about.com]. If we say that there were 86,400 seconds in a day (24 hours * 60 minutes/hour * 60 seconds / minute), then someone standing on the equator was moving at 0.288212384259259 miles per second. Taking into account the shorter day, we are now moving at 0.288212393199181 miles per second, a difference of 0.000000008939921 miles per second.

      To determine time dilation, we look at the lorentz transformation, 1/sqrt(1-(v*v)/(c

  • Linux Kernel Patch (Score:4, Funny)

    by krbvroc1 ( 725200 ) on Tuesday January 11, 2005 @11:23AM (#11321489)
    I've submitted a kernel patch to adjust the 'gettimeofday' POSIX function to account for this 2.68 microseconds. Most of you wont notice a difference, but for real-time applications, this can be a significant interval. We probably need to add some additional 'daylight savings' flag adjustments for applications that do / don't want this adjustments.
  • Oh, shit, I dropped a CD to the floor, can someone calculate how that affects Earth rotation? Yes, it's a big event, but it is so much smaller than (EG) this: http://en.wikipedia.org/wiki/Krakatoa [wikipedia.org]. I read that they was tracking climate changes caused by this in _Europe_ 5 years after the event.
  • Ok, so if the Earth is rotating faster, and it's mass stays the same, then the Earth-ward force should be reduced. The faster the planet spins, the more intertia I have. The more inertia I have pulling me away from the planet, the less the effects of gravity (acting as a centripital force) would be felt.

    Am I missing anything, or do I weigh a fraction of a fraction of a pound less?

    ~D
    • The faster the planet spins, the more intertia I have. The more inertia I have pulling me away from the planet, the less the effects of gravity (acting as a centripital force) would be felt.

      There's nothing pulling you away from the planet! The planet is pulling on you.

      The earth exerts a gravitational force on you. Some of this force is used up by keeping you along a circular path as the planet rotates. The rest is what you sense as "gravity."

      Weight is defined as the force of gravity on an object. Si

  • Like how many of these earthquakes have happened? What's THEIR contribution to altering the Earth's rotation?

    Assuming that these earthquakes are completely random, and have a more or less uniform distribution (well, actually around the limits of the tectonic plaques), I assume that in average the earth will have the same rotation speed. Some earthquakes will accelerate it, others will slow it down.

    This earthquake just happened to be the first one whose effects could be MEASURED. First sample, doh?

    Frankly this "oh wow look! the earthquake was so powerful it affected the rotation speed of the Earth!" stuff makes me laugh.
  • Then again, I wish I had that much free time on my hands. OK which one of the guys is gonna re-adjust all those atomic clocks :P.
  • It's amazing how this study has been transformed by people, like a bad game of "telephone."

    I had to answer a question from someone who'd heard that our days were now 2 seconds shorter.

    On top of that, the numbers are based on a model, not measurements. The length of a day can't even be measured to better accuracy than 20 microseconds.

    And then there's the fact that the natural tendency of the planet is to slow its rotation due to tidal drag. You should get back your 3 microseconds within a reasonable time.

  • I actually rtfa (gasp!) and wonder why I bothered. The Nasa press release repeats the author's claim but gives absolutely no details that enable anyone to make a reasonable conclusion as to the claim's veracity. You know, things like, are we talking about observed motion or some guy's model spit this prediction out. The article doesn't say nor does it link to a paper or preprint.

    This idea first popped up in sci.geo.earthquakes shortly after the quake. At the time I figured that for the earth to slow down, t

  • First, I believe the Sun and Moon perturb the Earth's rotations at perigee and appogee in terms of miliseconds. Wouldn't the effect of these two bodies "wash" the any microsecond change in the rotation of Earth?

    Second, what about the conservation of energy? If the angular moment of Earth changed (according to the article earth speed up) where did the energy come from? For the Earth to speed up, energy has to be added to the angular moment of Earth. Even if a chunk of the Earth's mass shifted somewhere

    • Re:Questionable Article? Conservation of Energy? (Score:5, Informative)

      by pclminion ( 145572 ) on Tuesday January 11, 2005 @11:58AM (#11322070)
      Second, what about the conservation of energy? If the angular moment of Earth changed (according to the article earth speed up) where did the energy come from?

      Wow, talk about screwed up thinking.

      It's precisely because of conservation of angular momentum that the rotation has increased! Angular momentum must stay constant. The radius of earth has decreased slightly. Thus, in order for the angular momentum to remain the same, the rotation must speed up slightly.

      Angular momentum is not the same as rate of rotation. NOT THE SAME!


    • IANAP (not a physicist), but I've noticed that when an ice skater spins and pulls in their arms, they spin faster. If the earth's overall density increases because a tectonic plate slides toward the center, then the Earth could presumably spin faster too.

      Perhaps it's a question of a shift in the ratio between potential energy and kinetic energy.

  • You now have 2.68 fewer microseconds each day to do whatever it is you do.

    In gaming terms: This is a difference of about .0000804 frames/second to the human eye. A pretty useless BIOS tweak.
  • I seriously thought it was a joke, but it wasn't. And, I'm actually not that surprised: Israel, U.S.A. and India have been blamed for causing the tsunami [crosswalk.com], according to Egyptian and other arab media.

    Wow.

  • I always new that science would find a way to increase my lifespan. I will no live to be... 2.68us*365days*50years=4 hundredths of a second older than expected!

    Thank you NASA and thank you US space program for making all this possible.

  • public funds well spent (Score:4, Funny)

    by Mantorp ( 142371 ) <mantorp 'funny A' gmail.com> on Tuesday January 11, 2005 @12:17PM (#11322389) Homepage Journal
    NASA scientists, using data from the Indonesian earthquake calculated it affected Earth's rotation, decreased the length of day, slightly changed the planet's shape, and shifted the North Pole by centimeters. The earthquake that created the huge tsunami also changed the Earth's rotation."

    What about the effects on the earth's rotation, didn't NASA scientists find anything on that? And I also read that the earth's rotation was affected, as well as the rotation of the earth.

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