Counting down to 2017 will take longer than usual this New Year’s Eve (2017) as horologists compensate for a slowdown in the Earth’s rotation.
While clocks normally goes from 23:59:59 to 00:00:00, the extra second is being added in between – and hi-tech digital clocks will record that time as 23:59:60.
A leap second last occurred in June 2015 and this will be the 27th time it has occurred. The change is required because standard time lags behind atomic clocks
Leap seconds can be a headache for communication networks, financial systems and other applications that rely on precise timing, and must be programmed into computers to avoid mistakes.
The International Earth Rotation and Reference Systems Service (IERS), based at the Paris Observatory in France, tracks the Earth’s rotation and announces when a leap second is needed roughly six months in advance.