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People gather outside Sendai station after a powerful earthquake hit northern Japan on Friday AP Photo/Kyodo News
Japan Earthquake
Massive Japanese quake causes day to shorten slightly
The earth’s rotation sped up by over a microsecond because of the 8.9 magnitude earthquake.
YOU WON’T NOTICE it, but the day just got a tiny bit shorter because of Friday’s giant earthquake off the coast of Japan.
NASA geophysicist Richard Gross calculated that Earth’s rotation sped up by 1.6 microseconds.
That’s because of the shift in Earth’s mass caused by the 8.9-magnitude earthquake. A microsecond is one-millionth of a second.
That change in rotation speed is slightly more than the one caused by last year’s larger Chile earthquake.
But 2004′s bigger Sumatra earthquake caused a 6.8-microsecond shortening of the day.
The Japan quake is the fifth strongest in world history since 1900.
- AP
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