I heard about this a few days ago, but I’ve been listening to the news on the radio pretty much continuously since the 8.9-magnitude earthquake struck off the coast of Japan on Friday. I just finally got around to finding an actual article about it.

According to NASA geophysicist Richard Gross, it turns out that the massive quake accelerated Earth’s spin enough to shorten the length of the day by 1.8 microseconds (a microsecond is a millionth of a second). The earthquake changed the distribution of the earth’s mass, shifting more of it towards the equator and thus causing the faster spin (like when you spin on a wheely chair and tuck your legs in to go faster. Don’t pretend you’ve never done it). The quake actually moved Japan’s main island about 8 feet. 8 feet. Think about how insane that is.

The Chilean earthquake last year also shortened earth’s day by about 1.26 microseconds, and the Sumatra earthquake in 2004 shortened it by 6.8 microseconds. Gross believes that the aftershocks, smaller but great in number, could have a cumulative shortening effect on earth’s day as well.

Crazy, no?