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NASA Details Earthquake Effects on the Earth
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.
Let me guess, those are missing in the night, right?
At least that would explain my lack of sleep lately...
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.
How am I supposed to fit a pithy, relevant quote into 120 characters?
Bartender, another Fort Garry Dark, and hurry!
Trolling is a art,
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
great, more time for people to do things like this
/* No Comment */
Now how am I supposed to find the time to get all those TPS reports done!
Here a Sig There a Sig Everywhere a Sig Sig...
You now have 2.68 fewer microseconds each day to do whatever it is you do.
Well, there goes my sex life.
calculated it affected Earth's rotation, decreased the length of day
Does this mean that NASA confirms that superman can indeed turn back time?
----
Squirrel
You now have 2.68 fewer microseconds each day to do whatever it is you do.
Yay! My first raise in pay since 2001!!
"If you think you have things under control, you're not going fast enough." --Mario Andretti
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?
If you're not outraged, you're not paying attention!
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.
Your hair look like poop, Bob! - Wanker.
Wow, the Tsunami increased my life expectancy by 50,713.6 microseconds.
~~~
Click here, you know you wanna!
According to this article the moon's orbit is causing our day to lengthen by about 2 milliseconds per century anyway. I, for one, am greatly relieved. ;-)
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!!!
"I don't know half of you half as well as I should like, and I like less than half of you half as well as you deserve."
Oh, don't flatter yourself. :)
2.68 fewer microseconds?
.0000784 fewer frames of Quake 3 each day!
Hell! That means I'll be able to render
A Call For A New Slashdot Moderation Level!
A CNN article 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.
Well they do have daily 2.68 usec loss to deal with you know. Ease up man.
BSD is designed. Linux is grown. C++ libs
I read on CNN science page 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.
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.
It is very common. For example, the duration of the day in summer is longer than in winter (no, I'm not speaking of the length of the light period, but of the rotation period of the earth). The reason is that the trees move mass upward in spring (they get leaves) and downwards in autumn (the leaves fall back down), which changes the moment of inertia of the earth. Since trees only grow on land areas, and most land areas are on the Northern hemisphere, this gives a net effect of slower earth rotation in (Northern) summer.
The Tao of math: The numbers you can count are not the real numbers.
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.
. . 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?
"I don't need drugs to enjoy this, just to enhance it" - Otto
i heard this two weeks ago...
I think the news here is that they've actually done the calculations. They knew it would change two weeks ago, but not what the final number would be. Slate's "Explainer" had an article on scientists' expectations of this right after the quake.
One man's -1 Flamebait is another man's +5 Funny.
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.
Where the fuck do kids learn this shit? Sorry to go off on you, but we get posts like yours every time any thread comes up involving "the earth".
This ball of rock has been here for 4.5 billion years. It ain't going nowhere it ain't gone for the past 4.5 billion years.
Conservation of angular momentum is not the same as conservation of mass. You can speed up the Earth's rotation by squeezing it into something shaped like a bowling pin, or you slow down its rotation by squashing it into a disc, but its orbit around the sun doesn't change unless you add mass to it. And that isn't going to change measurably unless you add so much mass that all life on it would be wiped out anyways. (Hint: We've been taking on a few tons of mass every day in the form of micrometeorites. OMGLOLZ TEH SUN GONNA EAT US... well, actually, not. The earth is a small planet, but it's still pretty fucking massive.)
The reason I'm going ballistic is that this is all basic physics that was figured out over 300 years ago. It's called science. If you're not learning it in school, walk up to your envirocuddly studies, creationist esteem, or whatever the fuck else bullshit they're teaching today teacher. When you're within three feet of that teacher, give him or her a royal bitchslap. They'll expel you. That means you can get out of the fuckin' schools and into a fuckin' library and start learning something.
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.
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.
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.
Don't blame me, I voted for Durga.
False. The gravitational pull of the earth attracts additional matter from space on a constant basis, so its mass is *always* increasing, even if the increase is barely measurable and totally imperceptible.
Self-referential sigs are rarely entertaining.
Increasing Earth's rotational inertia would decrease angular velocity, which would LENGTHEN the amount of time required to complete one revolution.
In this case, the quake caused some settling to occur in the plates, which caused rotational inertia to decrease, angular velocity increased, and the day shortened.
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!
Your working 2.68 microseconds less each day, but getting paid the same, so technically you got a raise! (provided you distribute thos 2.68 microseconds evenly among the hours your working and not playing WoW)
Yes Francis, the world has gone crazy.
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.
See, the reason the Earth is moving slower is because the average equatorial bulge grew a tiny bit, thus slightly reducing the gravitational attraction for those living on the equator. Therefore, due to general relativity, time will now move a little faster due to local weaking of the gravitational field except that this is exactly canceled out by time moving a little slower due to SR affects caused by moving a tad faster. (OK, I made up the exactly canceling out bit - but it might be true! And, I also made up the equatorial bulge bit, too. OK, I totally didn't RTFA, and am really just making most of this up.)
Ben Hocking
Need a professional organizer?
I honestly don't know, but I am curious.
Hmm, I guess it does. A bit of looking at the Straight Dope reveals:
Dear Cecil:
Is the earth getting heavier or lighter? After all, we've littered the cosmos with a lot of NASA stuff, which should shave off a few pounds, along with vapor escaping from the atmosphere. On the other hand, there's a lot more people and meteorites around than there was in 8011 BC. What do you think? --Edward M. Smith Jr., Los Angeles
Dear Edward: Puny humanoid, you think the pitiful efforts of mankind have appreciably altered the mass of the earth, reliably estimated at 6 sextillion, 588 quintillion tons? (And man, if you don't think it was a bitch getting that puppy on the scale...) If so, shed your illusions. It's believed the earth gains anywhere from several dozen to several hundred tons per day due to meteorites and meteoritic dust--10,000 to 100,000 tons a year. (Sorry, but estimates vary widely.) This far exceeds any losses. The weight of the people, incidentally, has increased the mass of the earth by zero, for the obvious reason that we are but dust, and unto dust we shall return. To put it another way, human cells are merely rearrangements of the compunds previously found (i.e., before dinner time) in plant cells and animal cells. Net change pound-wise, nada.
Explain the proverbial ice skater who speeds up her spin as she pulls her arms toward her body. According to you, this can only explained by "adding energy" (what energy?) or "removing stuff" (she lost mass?!)
For some bizarre reasons you seem to think that the r in L=r x p is a constant. It isn't. The earth contracted somewhat after the earthquake, bringing mass closer to the center of rotation and decreasing the moment of inertia.
Your understanding of this stuff is very incomplete.
That means I'll be able to render .0000784 fewer frames of Quake 3 each day!
The world mourns your tragic daily loss of eight dozen pixels, but we mock your loss of a social life due to Quake 3 addiction.