LEAP SECOND TIME ADJUSTMENT DAY
Leap Second Time Adjustment day is listed as an observance title only. Some years scientists do not make adjustments. But, if they do, then it’s done on either June 30 or December 31.
The majority of the world measures time solely based on a 24 hour day in which each hour contains 60 minutes and each minute contains 60 seconds. That measurement is much too simple for accurate time measurement.
Scientists since about 140 AD have attempted to break down the hours in the day into a consistent and precise means of measure. Due to the variability of the Earth’s rotation, measurement of the 24 hour day is not an exact science. There is some dispute over the validity of leap second adjustments. Some years scientists do not make adjustments. But, if they do, then it’s done on either June 30 or December 31.
HOW TO OBSERVE
Use #LeapSecondTimeAdjustmentDay to post on social media.
The leap-second system was first introduced in 1972.
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