Tuesday, June 30, 2015

Why Yes, I'll Take An Extra Second!

Congratulations! On July 1, 2015, you will live for one second longer. Why, you ask? Because we'll be experiencing not a leap year, but a leap second.

Surely, you're scratching your head at this point. I'll explain.


As the Earth rotates on its axis, we mark a day as one complete revolution. In twenty-four hours, the Sun will make one lap through our sky. Though, it's not exactly twenty-four hours. In the early 1900's, astronomers determined that a day was a fraction off from being exactly twenty-four hours long. This is due to the rotation of our planet not being completely constant. Various factors drag upon the spin of Earth. Overall, our planet's rotation is slowing down, second by second. A chief influence upon Earth is our own moon, which pulls upon us with tidal forces. Other natural events, like earthquakes and volcanic eruptions, shift us off the rotational axis in very minuscule, but noticeable amounts.

Thereby, our days because shorter in a mathematical sense. If we didn't insert a leap second, over time the day would become warped and not match current measurement standards.

Surprisingly, this isn't the first time a leap second has been used. Since 1972, we've had twenty-five other instances of the leap second being inserted. More than likely, you won't notice the added second at all. Your day will continue on as planned, not being affected in the slightest. This doesn't hold true for computers and network systems, where an extra second can wreak havoc. When the last leap second was employed in 2012, it caused airline problems and sent many popular websites offline temporarily.

I find it amazing how one second can have so much power, yet never be noticed. Perhaps the next time you glance down at your watch, you'll reconsider how important a second really is.

No comments:

Post a Comment