No Leap Second for the UK

The Guardian, the Times, the Mail and all the others have got it wrong: when most of the world experiences a leap second on the stroke of the New Year, and all their clocks need adjusting, the UK's clocks can carry on regardless.

Zapperz over in the US at the Physics and Physicists blog has the same story.

A Leap Second At The End of 2008

Don't celebrate too soon for 2009. 2008 is going to be 1 second longer than you expected due to a leap second.
"On New Year’s Eve, the international authorities charged with keeping precise time will add a single second to our lives. It will be the 24th “leap second” since 1972, and the first since 2005." (NY Times)
Or you can kiss someone one second longer at midnight. :)

To give Zapperz some dues, the USA bases its time standard on Coordinated Universal Time (UTC), so our friends over the pond will benefit from the extra second.

Sadly, in the UK our kisses must be of the usual length. :(

The leap second applies to UTC (Coordinated Universal Time, based on the atomic clock standard), and it is needed to bring UTC into line with Universal Time (specifically UT1), which is based on observed mean solar time at the Greenwich meridian (Greenwich Mean Time) and so the Earth's rotation.

Unfortunately, the UK's time standard is defined in law as GMT (a.k.a. UT1). Similarly, anyone else whose time standard is UT1, such as Ireland, Canada and Belgium - so no leap second for us.

However, even though GMT is the UKs legal time standard, the National Physical Laboratory has one of the world's most accurate clocks and contributes to the International Atomic Time standard. The long wave time signal, broadcast from Anthorn Radio Station in Cumbria, is a UTC signal, while the internet and GPS clocks all depend on the same atomic time standard.

GMT, then, (as an Earth based time) is not used in reality anymore, despite its official designation as the source of British time.

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