Science and Space

space and astronomy articles.

Indonesian earthquake changed Earth’s perimeters.

NASA scientists have calculated that the Indonesian earthquake of Dec. 26, 2004it slightly changed our planet’s shape, shaved almost 3 microseconds from the length of the day, and shifted the North Pole by centimeters. According to latest calculations, the Dec. 26th earthquake shifted Earth’s "mean North Pole" by about 2.5 centimeters (1 inch) in the direction of 145 degrees east longitude, more or less toward Guam in the Pacific Ocean.

The quake also affected Earth’s shape. Earth’s oblateness (flattening on the top and bulging at the equator) decreased by a small amount—about one part in 10 billion. This continues the trend of earthquakes making Earth less oblate. Less oblate means more round.

It is also found the earthquake decreased the length of the day by 2.68 microseconds. (A microsecond is one millionth of a second.) In other words, Earth spins a little faster than it did before. This change in spin is related to the change in oblateness. It’s like a spinning skater drawing arms closer to the body resulting in a faster spin.

But please note that none of these changes have yet been measured—only calculated. But scientists hope to detect the changes when Earth rotation data from ground based and space-borne sensors are reviewed.

posted by: kyawoo at 20:17 | link | comments (5) |
earth

Comments:

#1  12 January 2005 - 20:19

 

Truly amazing. It really is something!

Jackal

#2  12 January 2005 - 21:37

 

This is how Pole shifts start .... and we are due!!

tracyv

Anonymous

#3  13 January 2005 - 11:44

 

does that mean i should set my alarm clock earlier for work

Anonymous

#4  16 January 2005 - 04:17

 

So before earthquakes ever occurred in the history of the world, it is conceivable that the Earth was flat! Haha. J/K.

Anonymous

#5  16 January 2005 - 07:10

 

This is fascinating data!

Anonymous

Comments: