Posted on 01/01/2005 9:38:48 PM PST by Coleus
Beyond killing tens of thousands and unleashing a humanitarian crisis of epic proportions, the twinned earthquake and tsunami that struck Southeast Asia Sunday altered the angle of the Earth on its axis, moved the North Pole, pushed walls of water throughout all the world's oceans and shifted the soil as far away as Newark, researchers are reporting.
Scientists said yesterday they are looking beyond the tragedy to try to extract meaning from an event of such magnitude. They want to learn how the Earth responds as a system to one of Nature's terrible jolts. And they wonder about the Earth's resilience.
Calculations performed by Richard Gross of NASA's Jet Propulsion Laboratory in California show that the quake sped up the rotation of the Earth and enlarged its wobble, causing the length of a day to shrink permanently by 3 millionths of a second. It also moved the North Pole 1 inch, he found.
Researchers at the Lamont-Doherty facility in New York, part of Columbia University, have been tracking earthquakes for decades and say their instruments showed that the quake rang the Earth like a bell. Seismic waves emanated from the epicenter, like ripples moving out from a pebble thrown onto a pond surface.
Armbruster, the Lamont-Doherty seismologist, said that, though he hasn't completed his analysis, he believes the quake moved the soil in the Newark and greater metropolitan area by a half- inch. The temblor on the other side of the world pushed the ground up that far, then back down the same distance. The movement was so swift, it was not noticed by residents of the region, he said.
A well-studied 1964 quake in Alaska of a greater magnitude moved the ground in New York up 2 inches and then down 2 inches, he said.
(Excerpt) Read more at nj.com ...
Thanks for the ping!
Ummm... Note quite how you describe it here. The Earth is slowing yes. But it is due to tidal interaction between the Earth/Moon system. Also indeed the Earth is slowing ever so slightly in its orbit about the Sun. However, to do this, it must recede from the Sun as described by Kepler's laws. The reason the Earth is receding ever so slightly is due to the tidal interaction of the Earth/Sun system. However, the estimated increase in our orbit is about one millionth of a meter per year. One other effect that is causing the Earth to recede is the nuclear processes inside the Sun. These processes cause the Sun to loose a little mass over time. However, this is also only a tiny effect on the Earth's mean distance from the Sun.
I was under the impression that the distance known as a parsec was the distance a star (or other object) needed to be in order to show a change of one arcsecond between observations at opposite sides of the earth's orbit. However, since the earth is not a constant distance from the sun, the average distance, or Astronomical Unit, is used as the basis for the orbital distance.
Cool!
Not me though. It was a nice picture I found for my post. :-)
Won't affect oil production since Bush has Halliburton on the job...
I understand why the unit of AU is replaced for a specific annual measurement - like you, I was assuming that paralax was measured from opposite sides of the orbit, rather than having a left parsec and a right parsec.
More important, what contingency plan does the DNC have for when the big one dumps most of California's blue parts into the Pacific?
No "Newark Shakes, Women & Children, Poor Affected Most, Bush's Fault" headline in the Star Ledger?
Baloney.
I have a good friend who earned his Ph.D at ISU in remote sensing. His dissertation was on using GPS and other data to track animal migrations.
The curious thing about looking at satellite images for years is that he can do a 1,000 piece jigsaw puzzle in a matter of minutes.
I think the confusion comes from the source not specifically saying that the measurement is from opposite sides of the orbit, or a total of 186 million miles apart (assuming we're measuring from the center of the sun, not the surface).
Here is a better description (has diagrams :-)) than I could write in a few sentences:
http://www.star.ucl.ac.uk/~idh/STROBEL/starprop/strpropa.htm
Nope. The parsec is related to one AU not two. See the link I posted for lepton.
Being that I did not alter my playlist on iTunes (the songs are still in the original running order there), there can be no other explanation. The earthquake is responsible for shuffling my Talking Heads playlist.
Whooohooo! :-) That field is growing by leaps and bounds.
I have a good friend who earned his Ph.D at ISU in remote sensing. His dissertation was on using GPS and other data to track animal migrations.
Just way cool! :-) I also work with people who have graduate degrees in remote sensing as well.
The curious thing about looking at satellite images for years is that he can do a 1,000 piece jigsaw puzzle in a matter of minutes.
WOW. I sure couldn't do it that fast! :-)
For the receding of the Moon, I (the author :-)) limited the description to the Earth/Moon system only.
The real story to me in this article is that we have instruments to measure this with some degree of certainty.
I was shifting through links like http://en.wikipedia.org/wiki/Parallax which describe parallax as the difference in angle between one extreme and another - which would be in keeping with my misunderstanding - and later the "Stellar Parallax" description which would be in keeping with the one you described.
Your link provided the Doh! moment for why the radius version would be the one used: Basic trig and the flagpole measurement example. :)
I guess that comes from reading a lot and never actually doing the calculations myself. If I had, that would have been obvious. Doh!
Went back to my old college textbook, and it is with renewed authority that I can say: "just damn". Nowhere do I see the AU doubled to use the diameter of the orbit. I had it wrong all this time, and there were enough other people out there under the same misapprehension to reinforce me.
Thanks, RA
Yes, Canada will still be socialist far into the future...
Seriously, the geographic North Pole does meander about a bit w/r/t the Earth's surface. This is an irregular motion, as opposed to the regular precession of the pole, where its projection in the sky sweeps an arc every 23,000 years or so, like a spinning top. That is why in about 14,000 years the "North Star" will be Vega in the constellation Lyra.
Is that why my compass keeps flashing 12:00 ? Where did I put that instruction booklet?
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