Time will never be the same again if the organisation responsible for setting the world's clocks votes this month in favour of a controversial plan to abolish the "leap" second - the extra second added to the time signal once every few years.
Experts from around the world are scheduledto vote on eradicating the leap second at a meeting in Geneva next week of the International Telecommunications Union, the United Nations agency responsible for timekeeping standards.
Debate about the leap second has raged for years but observers believe this ballot could mark its final demise, although not before another one is added to the midnight signal on June 30 this year.
The leap second was first introduced in 1972, and since then has been used on 24 occasions to keep astronomical time - which is based on the rotation of the Earth - in synchrony with international atomic time, based on the highly regular vibrations of a caesium atom.
Leap seconds were introduced because the rotation of the Earth is slowing down by about two-thousandths of a second per day, which means that without leap seconds atomic time would go an extra second ahead of astronomical time once every 500 days or so.
When necessary, a leap second is added to atomic time to decrease the difference between astronomical time and co-ordinated universal time (UTC).
Many organisations, including Britain's Royal Observatory, have been happy with the leap-second arrangement to keep astronomical time in harmony with atomic time. But other organisations, such as the International Bureau of Weights and Measures in Paris, are not.
"There is little support for [the proposal] here in Britain," said Jonathan Betts, senior curator of horology at the Royal Observatory. "We feel that it's important not to lose the link between the measurement of time and the Sun, which has been fundamental to the human timescale ... It would disconnect us from nature."
Those in favour of abolishing the leap second argue that many critical systems, such as the GPS instruments used in aircraft navigation, depend on highly accurate timekeeping which might fail if people forget to update them.