Decision put off on leap second, ending atomic clock sync with Earth day

GENEVA — The leap second may live on for at least another three years.

Once or twice a year, the leap second can be tacked on to synchronize atomic clocks — the world’s scientific timekeepers — with the Earth’s rotational cycle, which does not run quite like clockwork.

Without the leap second, atomic clocks would diverge about a minute a century from the course of the sun across the sky.

Britain, China, Canada and others have argued to keep it, but the United States, France and other nations have pushed to untether machines from the natural cycle because of the technical difficulties and costs to government and business.

Sanjay Acharya, a spokesman for the International Telecommunication Union, said Thursday a decision to abolish the leap second has been put off until next week. He said “it’s been deferred” because government delegates at an ITU meeting were unable to reach agreement at talks this week.

The decision about how much the world needs the leap second affects everything from mobile phone networks to financial markets to air traffic control systems, all of which rely on atomic clocks and wouldn’t have to momentarily stop their systems.

A Paris-based agency that tracks the globe’s irregular wobble sends notice when the world’s timekeepers need to add a leap second. That’s only done on June 30 and December 31, but sometimes years go by without an adjustment — and there’s never been the need to subtract a leap second.

Government delegates now plan to examine the issue at a separate meeting in Geneva next week, but Acharya said they will likely defer any formal decision until 2015.


By Associated Press, Published: January 19

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