Science

Earth's Days Are Slowly Getting Longer Every Century

By Christie Abagon , Dec 09, 2016 01:48 AM EST

Here's goods new to people who wish their days were longer - literally - or not.  Astronomers revealed that the Earth's days are indeed getting longer, but you are not likely to notice it soon, since it would take about 3.3 million years to gain just one minute.

Duncan Agnew, a geophysicist at Scripps Institution of Oceanography in San Diego, who is not involved in the study said: "There is time and then there is how fast the Earth spins.  Traditionally those things are closely linked, but they are not the same."

Your Clock May Actually Be Seven Hours Late

In a report published in Proceedings of the Royal Society A., astronomers found that the Earth's rotation to its axis has slowed down by 1.8 milliseconds per century, or a discrepancy of about seven hours over the course of 2 1/2 milleniums.  This means compared to 700 BC, our clock today is 7 hours late. 

"Even though the observations are crude, we can see a consistent discrepancy between the calculations and where and when the eclipses were actually seen.  It means Earth has been varying in its state of rotation," Leslie Morrison, from Durham University and the UK's Nautical Almanac Office, told the Guardian

Earth's Slowdown Is Caused By The Moon's Tidal Pull

The reason why Earth's rotation is slower now? Morrison said, blame it on the moon.  The moon's tidal pull is acting like a drag on our planet, a process called tidal braking.

"The heaping up of water drags on Earth as it spins underneath," Morrison said.

But it's not just because of the moon's tidal pull.  The Earth's sea levels as well as electromagnetic forces between Earth's core and its mantle also play a role on the Earth's spin. 

"These estimates are approximate, because the geophysical forces operating on the Earth's rotation will not necessarily be constant over such a long period of time. Intervening Ice Ages etcetera will disrupt these simple extrapolations," Morrison concluded.

Related Articles

© 2020 ITECHPOST, All rights reserved. Do not reproduce without permission.
Real Time Analytics