The distribution of Earth's mass due the shifting tectonic plates around Japan was so significant that the speed of the planet's rotation has increased: "The intense temblor has accelerated Earth's spin, shortening the length of the 24-hour day by 1.8 microseconds, according to geophysicist Richard Gross at N.A.S.A.'s Jet Propulsion Laboratory in Pasadena, California. ... The scenario is similar to that of a figure skater drawing her arms inward during a spin to turn faster on the ice. The closer the mass shift during an earthquake is to the equator, the more it will speed up the spinning Earth."