Feeds

2008 goes into one-second overtime

Boffins insert another 'leap second'

The smart choice: opportunity from uncertainty

As if the leap day in February wasn't enough stalling for time, scientists intend to delay the arrival of 2009 by one additional second.

Timekeepers will tack on a "leap second" to the world's clocks December 31, 2008 at 23 hours, 59 minutes and 59 seconds Coordinated Universal Time (UTC).

The occasional chrono-adjustment is meant to keep the uniform time kept by atomic clocks since 1972 less than 0.9 seconds within the time-scale measured by the Earth's rotation around its axis.

The time discrepancy is due to the planet's spin gradually but surely slowing down, mostly due to tidal friction.

Solar timekeeping became somewhat of an antique when atomic clocks made their debut - measuring time on a more stable basis of the microwave signals electrons emit when they change energy levels. But old habits die hard, and mean solar time (UT1) is still used quite frequently to this day.

Under the International Systems of Units, an atomic time-scale second is defined as "equal to the duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom."

Leap seconds essentially pause UTC so UT1 can catch up.

The International Earth Rotation and Reference Systems Service (IERS) is in charge of monitoring the difference between the time-scales, and occasionally adding or removing a second to UTC to keep the two consistent.

Since 1972, there have been 24 leap seconds added to the UTC time scale. Leap seconds are inserted in varying intervals from once every six months (15,778,463 seconds) to seven years (220,898,482 seconds).

The most recent leap second was inserted in December, 2005. We suggest you adjust your New Year's eve plans to compensate for the several million yoctoseconds you'll now have to spare. ®

The Power of One Infographic

More from The Register

next story
World Solar Challenge contender claims new speed record
One charge sees Sunswift travel 500kms at over 100 km/h
Vote now for LOHAN's stirring mission patch motto
Does the shed actually know no bounds, or what?
SMELL YOU LATER, LOSERS – Dumbo tells rats, dogs... humans
Junk in the trunk? That's what people have
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
Beancounters tell NASA it's too poor to fly planned mega-rocket
Space Launch System would need another $400m and a lot of time
Jurassic squawk: Dinos were Earth's early FEATHERED friends
Boffins research: Ancient dinos may all have had 'potential' fluff
prev story

Whitepapers

Top three mobile application threats
Prevent sensitive data leakage over insecure channels or stolen mobile devices.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.