Monday, September 7, 2009

Leap Seconds

Time is what prevents everything from happening at once.

Since a year is actually 365.24219 days long, a day is added to the end of February, every fours years (except for years which are both divisible by 100 and not divisible by 400) ) to keep the calendar year in synchronization with the four seasons. When a day is added, that year is referred to as a leap year.

In mankind's quest for order in the universe, we also have leap seconds to keep clocks in synchronization with the rotating actions of the Earth.

In a perfect world, it would take exactly 24 hours for the Earth to rotate completely on its axis. However we no longer live in a perfect world, and probably never did. It seems that the moon's gravity has been slowing down the Earth's rotation these days. Naturally, this causes major concern for those with nothing better to do with their lives than seek perfection in universal timekeeping.

To solve this dilemma, the International Earth Rotation and Reference Systems Service, a group of global timekeeping regulators, adds an extra second to all clocks on the planet in order to keep them in sync. This event takes place every few years, on New Year's Eve or the last day of June. The last such occurrence was in 1998.

However, no good deed goes unpunished. On January 1, 1996, the addition of a leap second caused computers at Associated Press Radio to start broadcasting the wrong tape. The Russian global positioning system broke down for 20 hours when attempting to add a leap second and a leap-second bug resulted in GPS receivers from Motorola Inc. displaying the time as half past 62 o'clock to customers. Plus there is a safety risk that the failure by programmers to add a leap second might shut down air traffic control systems.

Because of numerous problems whenever a leap second is added, Dennis D. McCarthy, Navy's "Director of Time," drafted a leap-second proposal on behalf of the U. S. Government to eliminate leap seconds. Ending leap seconds would in effect cause the sun to rise later and set later by a factor of a few seconds each decade. This proposal was presented secretly to the International Telecommunications Union of the United Nations in 2004.

When word began to leak out about the proposal, it caused an uproar among astronomers. Daniel Gambis, the Earth Rotation Service's leap-second chief at the Paris Observatory, called it an "intrusion into scientific dialog" and another American power play. Ninety percent of his colleagues surveyed agreed.

The problem is that modern telescopes use the exact time and the Earth's position for aiming purposes when directing the system to point to a specific star. Astronomers argue that removing the link between time and the sun would require making changes to their telescopes at a cost between $10,000 and $500,000 per facility.

From 1884 to 1961, the world set its official clocks to Greenwich Mean Time which is based on the actual rise and set of the stars as seen from the Royal Observatory in Greenwich, just outside London. In 1961, the world changed to the current Coordinated Universal Time tied to extremely precise atomic clocks and began to add leap seconds to keep the official time within one second to Greenwich Mean Time. But the U. S. proposal of eliminating leap seconds would cause the world's official time to slowly drift away from Greenwich Mean Time.

Abolishing leap seconds is vigorously opposed by the British. Some British politicians fear it will further exacerbate the general anti-Europe feeling that has been festering since the advent of the European Union.

To add a leap second or not to add a leap second, that is the question -- whether it is nobler in the mind to suffer the slings and arrows of astronomers and the Brits, or to take arms against a sea of troubles caused by unforeseen glitches.

If this is a major quandary in your life, perhaps you should switch to decaf.

In a world of madness and chaos, a few seconds here and there hardly matters to most of us. Personally, I hope they add an hour or two to every day – I can use the extra sleep.

If time flies when you’re having fun, it hits full throttle when you don’t have enough of it. Time is the Great Teacher that kills all its students, to be reborn yet again and again.

Time is infinity -- a figure eight. At its center is the Point of Eternal Return.
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Quote for the Day – “Supposedly time heals all wounds, but you actually have to heal them yourself.” Bret
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Bret Burquest is an award-winning columnist and author of four novels. He lives in the Ozark Mountains with a dog named Buddy Lee and where time is always now. His blogs appear on several websites, including www.myspace.com/bret1111
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