2012-06-29

Leap Second

PhysOrg has an update on when the next "leap second" will be added to the world's timekeeping systems.
A leap second will be introduced on 30 June 2012 following a decision made by the International Earth Rotation and Reference Systems Service (IERS) earlier this year. This could potentially be one of the last ever leap seconds added, as a decision may be made in the next few years to abolish the practice.
So tomorrow will be 86,401 seconds long. Try not to panic.
Leap seconds are added to Co-ordinated Universal Time (UTC) to keep the time scale from atomic clocks within one second of that determined by the rotation of the Earth. The time scale produced by atomic clocks is much more stable and reliable than that based on the Earth's rotation, and without leap second adjustments the two would diverge by ever increasing amounts.
That would be bad. Wouldn't it?
There is ongoing debate over whether or not to abolish leap seconds and allow atomic time to gradually drift away from solar time. For now, a decision has been deferred until 2015, but if agreement is reached then to abolish the leap second, the second added on 30 June 2012 could be one of the last.
Brace yourselves. But I've got to say, the arguments for doing away with the leap second sound pretty compelling:
Some countries have proposed that leap seconds should be abolished because of the difficulties they cause for systems reliant on precise timing, and the time and effort needed to programme them manually into equipment, with the resulting risk of human error. They also argue that the need for predictable timekeeping outweighs that for a link between civil timekeeping and the Earth's rotation.
I wholeheartedly agree. And while we're on the subject, maybe we can finally kill off Daylight Saving Time.