2016 will go on a little longer.... It is time for a leap second! [View all]
The year 2016 will last a little longer. Youll need to wait a second!
As massive as our planet is, the Earth still brakes for ocean waves. Remarkably, this pale blue dot decelerates thanks to the braking action of ocean tides. In fact, our planet decelerates 2 milliseconds per day per century, according to the Naval Observatory. The final effect is that the planets rotation slows compared to atomic clocks.
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But since the world slows by about 2 milliseconds a day, a leap second needs to be added about every 500 days. Civil time must be adjusted so that the worlds atomic clocks do not vary from the Earths rotational time by more than 0.9 seconds, according to the observatory.
Said Geoff Chester: By adding a leap second, were essentially stopping our atomic clocks to let the Earth catch up.
More at link:
https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/12/28/on-dec-31-an-extra-leap-second-will-be-added-to-our-universal-clocks-because-waves/?postshare=5281482953246661&tid=ss_tw&utm_term=.2539db5cb43e