because of quake we might have to add a "leap second"

[donsu]

http://news.independent.co.uk/world/science_technology/story.jsp?story=596798


Quake shook Earth to core, say scientists


The quake that set off the devastating tsunami literally shook the Earth to its core, scientists believe, accelerating its rotation and shortening days by a fraction of a second. It may be necessary to add a "leap second" in years to come in order to correct the change.

-snip-

Richard Gross, a geophysicist with Nasa's jet propulsion laboratory in California, said he believed a shift of mass towards the Earth's centre caused the planet to spin three microseconds - one millionth of a second - faster. It also caused the planet to tilt around 2.5cm on its axis.

" had the effect of making the Earth more compact and spinning faster," he said, saying that the changes were too slight to be detected by global positioning satellite networks.

-snip-

Geologists said changes on the Earth's surface were more noticeable, shifting the island of Sumatra 36 metres to the south-west. Ken Hudnutt of the US Geological Survey said: "Some of the smaller islands off the south-west coast of Sumatra may have moved to the south-west by about 20 metres."
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I saw this article at:

http://www.scitechdaily.com/

[flyingfysh]

1. it's the other way around

If the days are shorter now, they may have to subtract a second somewhere.

[StClone]

7. I think they add a fraction of a second

To make up for the fact that Earth's solar rotation has not changed. However there are now more rotations (by a fraction of a second) per revolution around the sun to keep things (year now = #seconds + new .000003 second) equal.

[48pan]

2. We all lost weight!!!

Since the earth is spinning faster, centrifugal force is trying to throw us from the surface of the earth.

[Bucky]

3. That news is making my hair stand on end

literally!

[rabid_nerd]

8. Wouldn't it be gravity is higher, so we weigh more?

if it stops we'd be thrown...

[ShaneGR]

9. Yes, the poster has it reversed, we're all fatter now... :-)

Increased spin increased gravity.

[proud patriot]

10. Actually I think we just got more dense

:silly: weighing the same but taking up less space . :think:

[48pan]

11. Gravity would not change since the mass is still the same...

Therefore, higher centrifugal force without an increase in the mass yields lower weight.

Weight is what is measured by a scale. Mass is absolute.

[vpigrad]

4. You need a math lesson..

That's 0.000003 seconds. It would take over 300,000 years before we would have to add a second.

[donsu]

5. it's not my math - it's the scientist's math

nt

[StClone]

6. I think the writer missed the decimal point. emo

[Shopaholic]

12. Well--this thread does prove what we already know-

the math and science skills of Americans are indeed sadly lacking! (I include myself in that, btw, I'm hopeless in either subject)!

[Zorro]

13. "Leap seconds" are actually added pretty regularly

for those applications that need that sort of information -- every 3 or so years, I think.

Calculating satellite ephemerides is one area where accurate timekeeping is required for precision positioning.