On February 27th, a massive 8.8 magnitude earthquake struck Chile off the shore of Maule. Since then, several aftershocks (each with a magnitude of around 5.5) have hit Chile as well.  Though this is extremely tragic, more bad news has come: the earthquake has impacted the duration of the day on Earth, by shortening it (oh no)!

Scientist from NASA said on Monday that the earthquake in Chile shifted the Earth from its axis about 3 inches from its normal location and therefore shortening the days by 0.00000126 seconds!  This change occurred because the Earth’s mass was shifted.  Think of the Earth as a spinning top: because the Earth is not a perfect sphere, sudden changes in mass can shift where the actual ‘top” is. The result, is a change in speed from the Earth’s original rotation.  In this case, the speed of rotation increased, so now we have shorter days.

Scientists believe that this wasn’t the first time the axis of the Earth has been altered or shifted.  The Sumatran earthquake in 2004, which set off a deadly tsunami, was a 9.1 on the Richter scale and may have moved the axis 2.76 inches and made the days shorter by 6.8 microseconds (a millionth of a second). 

However this isn’t the end, the Earth can also increase the length of its days.  The moon recedes from Earth at a rate of 3.8 centimeters per year, increasing the length of days (we’re saved)!

[source]

by Billy F.

Posted in 2009 - 2010 Archives |