The earth's movements is slowing down by two thousandths of a second each day, which means astronomical time is out of sync with atomic time.
To reconcile this difference we have leap seconds, extra seconds which we add to time measurements every few years.
If we abandon leap seconds, and rely only on atomic clocks, time measurements will start to deviate from the position of the sun in the sky.
In thousands of years, clocks might say its midday in the middle of the night, but that is quite a long time away.
Horologists, experts on time, are debating the effects of the extra few seconds that have been added each year.
Al Jazeera's Barnaby Phillips reports from London.
Source: Al Jazeera