A U.S. scientist says this week's powerful Asian earthquake may have permanently accelerated the Earth's rotation and caused the planet to wobble on its axis.

Richard Gross, a geophysicist with NASA's Jet Propulsion Laboratory in California, claimed on Wednesday that a shift of mass toward the Earth's center during the recent quake caused the planet to spin 3 microseconds, or 3 millionths of a second, faster and to tilt about an inch on its axis.

Gross said that when one huge 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.