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The earthquake that killed more than 700 people in Chile on Feb. 27 probably shifted the Earth’s axis and shortened the day, a National Aeronautics and Space Administration scientist said.

Earthquakes can involve shifting hundreds of kilometers of rock by several meters, changing the distribution of mass on the planet. This affects the Earth’s rotation, said Richard Gross, a geophysicist at NASA’s Jet Propulsion Laboratory in Pasadena, California, who uses a computer model to calculate the effects.

“The length of the day should have gotten shorter by 1.26 microseconds (millionths of a second),” Gross, said today in an e-mailed reply to questions. “The axis about which the Earth’s mass is balanced should have moved by 2.7 milliarcseconds (about 8 centimeters or 3 inches).”

…

“It’s what we call the ice-skater effect,” David Kerridge, head of Earth hazards and systems at the British Geological Survey in Edinburgh, said today in a telephone interview. “As the ice skater puts when she’s going around in a circle, and she pulls her arms in, she gets faster and faster. It’s the same idea with the Earth going around if you change the distribution of mass, the rotation rate changes.”

Read the whole story in this Bloomberg filing reprinted on BusinessWeek.com.

As we re-synchronize our watches, we might recall that it was on this date in 1977 that the rings around Uranus were discovered.  In fact, in 1789 William Herschel had discussed possible rings around the seventh planet.  But it was only 23 years ago that, using the Kuiper Airbourne Observatory, the rings– 13 bands of extremely dark particles, varying in size from micrometers to a fraction of a meter– were definitively observed.

Hubble Space Telescope photo of Uranus, its rings, and its moons