‘Quake may have made Earth wobble’

The deadly Asian earthquake may have permanently accelerated the Earth’s rotation – shortening days by a fraction of a second – and caused the planet to wobble on its axis, US scientists say. Richard Gross, a geophysicist with NASA’s Jet Propulsion Laboratory in California, theorized that a shift of mass toward the Earth’s centre during the quake on Sunday caused the planet to spin 3 microseconds, or 3 millionths of a second, faster and to tilt about an inch on its axis. When one huge tectonic plate beneath the Indian Ocean was forced below the edge of another “it had the effect of making the Earth more compact and spinning faster,” Gross said. The Earth’s poles travel a circular path that normally varies by about 33 feet, so an added wobble of an inch is unlikely to cause long-term effects, he said. reuters

[For further information visit the International Earth Rotation and Refrence System (IERS) wbsite at http://www.iers.org/ ]
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