# Quake Likely Shifted Earth’s Axis 3" **URL:** \ **Category:** Factual Questions\ **Created:** [March 2, 2010, 1:16am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942 "2010-03-02T01:16:00Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![bonitahi](https://avatars.discourse-cdn.com/v4/letter/b/7993a0/32.png) [@bonitahi](https://boards.straightdope.com/u/bonitahi)\ **Post date:** [March 2, 2010, 1:16am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/1 "2010-03-02T01:16:00Z")
“Chilean Quake Likely Shifted Earth’s Axis, NASA Scientist Says” March 1 (Bloomberg) – “The earthquake in Chile on Feb. 27 probably shifted the Earth’s axis and shortened the day, a National Aeronautics and Space Administration scientist said. The axis about which the Earth’s mass is balanced should have moved by about 8 centimeters or 3 inches.” Shortened the day? I take that to mean that we all get to live longer now- or at least die later. Maybe we can squeeze in an extra Yankee game or whatever 🙂 Is that likely or even possible that the earth’s axis moved that much? ---
**Author:** ![Simplicio](https://avatars.discourse-cdn.com/v4/letter/s/c37758/32.png) [@Simplicio](https://boards.straightdope.com/u/Simplicio)\ **Post date:** [March 2, 2010, 1:21am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/2 "2010-03-02T01:21:59Z")
You think NASA is lying? ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [March 2, 2010, 1:42am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/3 "2010-03-02T01:42:46Z")
[For the Indonesian Quake:](http://www.jpl.nasa.gov/news/news.cfm?release=2005-009) > [@](#): > > January 10, 2005 > Gross and Chao have been routinely calculating earthquakes’ effects in changing the Earth’s rotation in both length-of- day as well as changes in Earth’s gravitational field. They also study changes in polar motion that is shifting the North Pole. The “mean North pole” was shifted by about 2.5 centimeters (1 inch) in the direction of 145 degrees East Longitude. This shift east is continuing a long-term seismic trend identified in previous studies. > > They also found the earthquake decreased the length of day by 2.68 microseconds. Physically this is like a spinning skater drawing arms closer to the body resulting in a faster spin. The quake also affected the Earth’s shape. They found Earth’s oblateness (flattening on the top and bulging at the equator) decreased by a small amount. It decreased about one part in 10 billion, continuing the trend of earthquakes making Earth less oblate. More from Dr. Gross at JPL: > [@](#): > > “The length of the day changes about a millisecond over the course of a year,” says Gross. “It gradually increases in the winter, when Earth rotates more slowly, and decreases in the summer. There are also longer patterns of changes in the length of day that last decades, even centuries.” [All Days Are Not Created Equal](http://www.jpl.nasa.gov/news/features.cfm?feature=15) ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [March 2, 2010, 1:51am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/4 "2010-03-02T01:51:53Z")
To give you a sense of perspective, according to the [article](http://www.irishtimes.com/newspaper/world/2010/0302/1224265432876.html) it shifted the axis by about 3 inches. The Earth’s diameter is almost 8,000 miles. The quake also shortened the day by about 1.26 millionths of a second. By contrast, a quartz wristwatch is accurate to about a [half-second per day](http://www.economicexpert.com/a/Quartz:clock.htm). ---
**Author:** ![Sapo](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Sapo](https://boards.straightdope.com/u/Sapo)\ **Post date:** [March 2, 2010, 2:01am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/5 "2010-03-02T02:01:31Z")
> [@Simplicio](#): > > You think NASA is lying? Well, after the whole moon lan… never mind. ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [March 2, 2010, 2:54am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/6 "2010-03-02T02:54:53Z")
I hope I’m farther south now. With my luck I shifted north. ---
**Author:** ![bonitahi](https://avatars.discourse-cdn.com/v4/letter/b/7993a0/32.png) [@bonitahi](https://boards.straightdope.com/u/bonitahi)\ **Post date:** [March 2, 2010, 4:14am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/7 "2010-03-02T04:14:21Z")
But, if the earth’s axis tilted three inches, as the _Bloomberg_ article states, wouldn’t we humans tend to tilt somewhat? Ensuing ramifications in human relationships and architectural engineering? ---
**Author:** ![bonitahi](https://avatars.discourse-cdn.com/v4/letter/b/7993a0/32.png) [@bonitahi](https://boards.straightdope.com/u/bonitahi)\ **Post date:** [March 2, 2010, 4:27am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/8 "2010-03-02T04:27:04Z")
Skuink…“Gross and Chao” That just sounds funny, sorry:) “oblateness” is cool, though. But seriously…3"? A change of 3 inches sounds really big to me! ---
**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\ **Post date:** [March 2, 2010, 4:27am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/9 "2010-03-02T04:27:41Z")
> [@](#): > > “The length of the day changes about a millisecond over the course of a year,” says Gross. "It gradually increases in the winter, when Earth rotates more slowly, and decreases in the summer. So the Northern hemisphere and southern hemisphere are rotating at different speeds. Man, that must generate some torque. ---
**Author:** ![bonitahi](https://avatars.discourse-cdn.com/v4/letter/b/7993a0/32.png) [@bonitahi](https://boards.straightdope.com/u/bonitahi)\ **Post date:** [March 2, 2010, 4:35am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/10 "2010-03-02T04:35:11Z")
> [@Blake](#): > > So the Northern hemisphere and southern hemisphere are rotating at different speeds. > > Man, that must generate some torque. Picture that. Whew! ---
**Author:** ![bonitahi](https://avatars.discourse-cdn.com/v4/letter/b/7993a0/32.png) [@bonitahi](https://boards.straightdope.com/u/bonitahi)\ **Post date:** [March 2, 2010, 5:13am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/11 "2010-03-02T05:13:46Z")
Back to the OP. What about the larger quake in Haiti? Did that alter the earth’s axis? In what direction? The same or opposite of the Chilean quake? Do they balance the normal axis out? As we all know there are many earthquakes per day in this world. Are they cumulatively moving the axis in a particular direction? Is there cause for concern because of them? What would be the consequences if the axis altered by one or two percent…or more, because of earthquakes? ---
**Author:** ![garygnu](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garygnu/32/2924_2.png) [@garygnu](https://boards.straightdope.com/u/garygnu)\ **Post date:** [March 2, 2010, 5:24am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/12 "2010-03-02T05:24:27Z")
> [@bonitahi](#): > > Back to the OP. > What about the larger quake in Haiti? Did that alter the earth’s axis? In what direction? … FYI, the Chile earthquake release about [500 times](http://www.thestar.com/news/world/article/772765--why-chile-dodged-haiti-style-ruin) more energy than the Haiti earthquake. Haiti was worse on the human loss and destruction scale. ---
**Author:** ![bonitahi](https://avatars.discourse-cdn.com/v4/letter/b/7993a0/32.png) [@bonitahi](https://boards.straightdope.com/u/bonitahi)\ **Post date:** [March 2, 2010, 5:50am UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/13 "2010-03-02T05:50:08Z")
“Haiti was worse on the human loss and destruction scale.” I know, much worse. It is so sad. And was much more disastrous. But, did that quake alter the earth’s axis to the extreme of the Chilean quake? ---
**Author:** ![DrFidelius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/drfidelius/32/3447_2.png) [@DrFidelius](https://boards.straightdope.com/u/DrFidelius)\ **Post date:** [March 2, 2010, 12:32pm UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/14 "2010-03-02T12:32:32Z")
No, the Haiti quake was much weaker, just closer to the surface, which is one reason it caused more damage. ---
**Author:** ![SenorBeef](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senorbeef/32/2220_2.png) [@SenorBeef](https://boards.straightdope.com/u/SenorBeef)\ **Post date:** [March 2, 2010, 1:24pm UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/15 "2010-03-02T13:24:38Z")
> [@bonitahi](#): > > But, if the earth’s axis tilted three inches, > as the _Bloomberg_ article states, > wouldn’t we humans tend to tilt somewhat? > Ensuing ramifications in human relationships > and architectural engineering? I’m not quite sure of the cause of your misunderstanding, but having the Earth’s axis rotate by 3 inches wouldn’t affect the way things lean or anything like that. When we talk about the tilt, we’re talking about the angle of the planet (from pole to pole) relative to the ecliptic on which it travels around the sun. It’s currently about 23.5 degrees, as [this picture](http://pauldeanno.com/wp-content/uploads/2009/08/earth_axis_0821.jpg) shows. We’re either 3 inches more or less tilted relative to the ecliptic now (not sure which it is), so instead of a 23.5 degree tilt we’re at (again if we’re talking about 3" of increased tilt) 23.50000000000000000000000000000000000000001 degrees (number made up). ---
**Author:** ![Pasta](https://avatars.discourse-cdn.com/v4/letter/p/ecccb3/32.png) [@Pasta](https://boards.straightdope.com/u/Pasta)\ **Post date:** [March 2, 2010, 1:50pm UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/16 "2010-03-02T13:50:34Z")
> [@bonitahi](#): > > But, did [the Haiti] quake alter the earth’s axis to the extreme of the Chilean quake? I would suspect that the nature of the quakes is rather important here. To change the rotational speed of the earth, you need to move mass either toward or away from the rotation axis. The Haiti quake occurred along a strike-slip fault, where two plates move primarily laterally alongside one another with very little next vertical motion. The Chilean quake occurred along a thrust fault, in which one landmass burrows under another. The latter would result in more significant changes in the earth’s moment of inertia. ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [March 2, 2010, 2:10pm UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/17 "2010-03-02T14:10:44Z")
> [@bonitahi](#): > > As we all know there are many earthquakes per day in this world. Are they cumulatively moving the axis in a particular direction? Is there cause for concern because of them? Seeing how we’ve survived earthquakes (and bigger ones than this) for 10,000 years I think we can safely say no. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 2, 2010, 2:12pm UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/18 "2010-03-02T14:12:08Z")
> [@Blake](#): > > So the Northern hemisphere and southern hemisphere are rotating at different speeds. > > Man, that must generate some torque. I’m pretty sure we had someone here a while back who argued that the two hemispheres were rotating in opposite directions, but I can’t find the thread. (It wasn’t **BZ00000** , who thought that [time would run backwards if the Earth’s spin was reversed](http://boards.straightdope.com/sdmb/showthread.php?t=140878)) ---
**Author:** ![Munch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/munch/32/5281_2.png) [@Munch](https://boards.straightdope.com/u/Munch)\ **Post date:** [March 2, 2010, 2:30pm UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/19 "2010-03-02T14:30:47Z")
> [@Blake](#): > > So the Northern hemisphere and southern hemisphere are rotating at different speeds. > > Man, that must generate some torque. I caught that as well. Any idea what that guy is on about? Can we take the rest of his comments seriously with a flub like that? I’d say that if I caught the error, it’s pretty egregious… ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [March 2, 2010, 3:04pm UTC](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942/20 "2010-03-02T15:04:07Z")
> [@SenorBeef](#): > > (again if we’re talking about 3" of increased tilt) 23.50000000000000000000000000000000000000001 degrees (number made up). 3" over 6371 km (radius) is 6.85 × 10^-7 degrees or 0.0025 arcseconds. That figure is just under the resolution limit of the [Keck interferometer](http://en.wikipedia.org/wiki/W._M._Keck_Observatory), 5 milliarcseconds. [Next page](https://boards.straightdope.com/t/quake-likely-shifted-earth-s-axis-3/530942.md?page=2)