Beacon Transcript – As some may have noted, a leap second was added to the last day of 2016 so as to re-sync atomic clocks with the planet’s rotational time.
Last night, everyone was waiting for the final countdown. At midnight, our planet said goodbye to 2016 and welcomed 2017. And it may have been hard to notice, but 2016 just wouldn’t end.
Last year was longer with just one second when compared to its predecessor. This is because 2016 saw both a leap year and a leap second.
A day usually has 86,400 seconds. December 31, yesterday, had 86,401. The difference was determined by the addition of a leap second.
Leap seconds are one-seconds adjustments to the UTC. The UTC or Coordinated Universal Time is occasionally in need of corrections. The adjustment is made so as to keep UTC as close as possible to UT1. UT1 is the mean solar time.
A correction system was implemented back in 1972. Since then, it has seen the addition of 26 leap seconds. The latest one was added last night, at 23:59:60 UTC. Such corrections are not individual to the end of the year.
Before the latest addition, another leap second was added back in 2015. It was introduced on June 30, at 23:59:60 UTC.
These extra seconds should help make up for the atomic clock inconsistencies. Such a device is a super-accurate human timekeeping method. They have a very precise and rigid second determination system.
In contrast, our planet is less rigid. Earth’s rotation, as a natural process, is somewhat less exact. Its rotation speed varies in accordance with certain factors.
Tidal friction is responsible for its rotation being a little off. The phenomenon is caused by the Moon’s tugging at our planet’s oceans.
UT1 and UTC are considered to be in sync when at a 0.9 second distance of the other. As such, the rotation variation led to the need of an extra second. The phenomenon, as aforementioned, is only occasional.
However, the need for leap seconds might increase over time. Scientists have known for some time that the Earth is slowing down. Back in 1972, research found that UT1 and UTC sported a 10 seconds difference,
In order to make up for the difference, scientists added 10 seconds to that year. 1972 was also the starting point of the time adjustment program.
Since then, an approximate discrepancy appearance period has been calculated. It was determined to appear anywhere in between 500 to 750 days. As such, a leap second is added so as to turn the clock back on track.
Human atomic clocks are based on cesium atoms. They vibrate very precisely and oscillate at exactly 9,192,631,770 times per second. Currently, Boulder, Colorado, houses what is considered to be the world’s most precise atomic clock.
This device is expected to lose a second only once every 100 million years. As such, it is much more exact that even our planet’s rotation speed.
Still, these highly-accurate are a recent development for humanity, so we should not brag about it.
As the leap second has been added to the UTC, most people have probably experienced it at quite another hour. For example, UTC 23:59:59 corresponds to 6:59:59 PM EST.
More exactly, the Eastern Standard Time saw a second added so as to re-sync UT1 with UTC in the United States. It came as an addition to the Washington, DC-based Master Clock Facility of the Naval Observatory.
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