A Smaller Earth

An argument has been released on December 28 that the earth has contracted and its rotation period permanently reduced, though insignificantly, due to the earthquake that hit the Southeast Asian region on December 26.

Reuters reported that researcher and geophysicist Richard Gross with the U.S. NASA’s Jet Propulsion Laboratory theorized, “The tectonic plate of the Indian Ocean has gone under the boundary of a different plate, which resulted in the earth’s ‘slight’ contraction and ‘miniscule’ acceleration of its rotation.”

Gross claimed, “Consequently, the rotation period of the earth, which used to be one rotation per day (24 hours), has been shortened by three microseconds (one microsecond is a millionth of a second).”

However, Reuters added that other scientists are countering his argument, saying, “These subtle changes are immeasurable.”

Seung-Ryun Kim srkim@donga.com