Saturday, December 27, 2008

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.

Or you can kiss someone one second longer at midnight. :)



Glen Thomas said...

"Or you can kiss someone one second longer at midnight. :)

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

The leap second applies to UTC (coordinated universal time, based on international atomic time), and is needed to bring it into line with Universal Time (specifically UT1), which is based on observed mean solar time and so the Earth's rotation.

Unfortunately, the UK's time standard is GMT (AKA UT1) - so no leap second for us (and anyone else whose time standard is UT1).

Tom said...

The leap second is at midnight UTC, so west of the Prime Meridian time zone, the second will have already been added.

And I'm pretty sure the UK is on UTC, officially. NPL seems to think so, at least

Glen Thomas said...

The 1978 Interpretations Act defines UK time as GMT, which is silly, since the NPL issues its version of UTC, most electronic systems use UTC, and the UK agreed that UTC should be the world standard for civil time when it was first developed.

There was a Bill put forward in the Lords in 1997 (The Co-ordinated Universal Time Bill) to correct the anomoly. It was passed by the Lords, but it ran out or time in the Commons (what's new?)

So we have a time standard that no-one uses, even if they think they do, because of a parlimentary oversight. But, since everyone is using UTC anyway, I don't think it really matters - we can all carry on as we were.

I won't be needing the 'pips' anyway this evening to mark the leap second - I can rely on the neighbours' fireworks for that.