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Scientists Help Create an Extra Second of Summer: Leap Second to Be Added On July 1, 2012

Rolland Arriza — Sat, 30 Jun 2012 10:11:35 +0000

Scientists at the National Physical Laboratory (NPL) will be adding a leap second at 00:59 BST on 1s

Behind the Times

Not Jack — Sat, 30 Jun 2012 04:02:03 +0000

One Second at a Time Which is to say that June 30th 2012 was 86,401 seconds long. An additional leap

Don't Miss It: Earth Adds Leap Second Saturday Night

brama1 — Fri, 29 Jun 2012 19:43:26 +0000

NEW YORK (CBSNewYork/AP) - What would you do with an extra second?

You’ll soon have one, so start planning.

Saturday night will stretch longer by a second. A leap second. International timekeepers are adding a second to the clock at midnight universal time Saturday, June 30, going into July 1. That’s 8 p.m. EDT Saturday. Universal time will be 11:59:59 and then the unusual reading of 11:59:60 before it hits midnight.

A combination of factors, including Earth slowing down a bit from the tidal pull of the moon, and an atomic clock that’s a hair too fast, means that periodically timekeepers have to synchronize the official atomic clocks, said Daniel Gambis, head of the Earth Orientation Service in Paris that coordinates leap seconds.

The time it takes the Earth to rotate on its axis — the definition of a day — is now about two milliseconds longer than it was 100 years ago, said Geoff Chester, spokesman at the U.S. Naval Observatory, keeper of the official U.S. atomic clocks. That’s each day, so it adds up to nearly three-quarters of a second a year.

Timekeepers add that leap second every now and then to keep the sun at its highest at noon, at least during standard time. This is the first leap second since January 2009 and the 25th overall. Gambis said the next one probably won’t be needed until 2015 or 2016.

There should be no noticeable affect or inconvenience on computers or any other technology that requires precise timekeeping because they adjust for these leap seconds, Gambis said Friday.

Earlier this year, official timekeepers from across the world discussed whether to eliminate the practice of adding leap seconds. They decided they needed more time to think about the issue and will next debate the issue in 2015.

So for now, Chester said, “you get an extra second, don’t waste it.”

How will you spend your extra second? Let us know.

Online:

Earth Orientation Center in Paris: http://bit.ly/LVB70Q

U.S. Naval Observatory: http://tycho.usno.navy.mil/leapsec.html

(TM and © Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

How Will You Spend Your Leap Second in 2012?

Randy — Fri, 15 Jun 2012 10:40:40 +0000

The International Earth Rotation and Reference Systems Service sent a Service de la rotation de la Terre confirming that an extra second will be added to June 30th, meaning we all will (hopefully) experience 30 June 2012 23h 59m 60s. If Leap Day featured Leap Dave Williams emerging from the Marianas Trench wearing blue and yellow to trade children’s tears for candy, what will this year’s Leap Second feature?

Tick tock ... tick - Extra second added to 2008

Webmaster — Sun, 28 Dec 2008 16:24:18 +0000

By Jim Wolf – 2 hrs 58 mins ago

WASHINGTON (Reuters) – Those eager to put 2008 behind them will have to hold their good-byes for just a moment this New Year’s Eve.

The world’s official timekeepers have added a “leap second” to the last day of the year on Wednesday, to help match clocks to the Earth’s slowing spin on its axis, which takes place at ever-changing rates affected by tides and other factors.

The U.S. Naval Observatory, keeper of the Pentagon’s master clock, said it would add the extra second on Wednesday in coordination with the world’s atomic clocks at 23 hours, 59 minutes and 59 secondsCoordinated Universal Time, or UTC.

That corresponds to 6:59:59 p.m. EST (23:59:59 GMT), when an extra second will tick by — the 24th to be added to UTC since 1972, when the practice began.

UTC is the time scale kept by highly precise atomic clocks around the world, accurate to about a billionth of a second per day, the Naval Observatory says. For those with a need for precision timing, it has replacedGreenwich Mean Time, or GMT.

The decision to add or remove a second is the responsibility of the International Earth Rotation and Reference Systems Service, based on its monitoring of the Earth’s rotation.

The goal is to make sure clocks vary from the Earth’s rotational time by no more than 0.9 seconds before an adjustment. That keeps UTC in sync with the position of the sun above the Earth.

Mechanisms such as the Internet-based Network Time Protocol and the satellite-based Global Positioning System depend on precision timing.

The first leap second was introduced into UTC on June 30, 1972. The last was added on December 31, 2005.

They have been added at intervals ranging from six months to seven years, Daniel Gambis, head of the IERS Earth Orientation Center at the Observatoire de Paris, wrote in an explanatory piece this month (http://hpiers.obspm.fr/eop-pc/).

Among the reasons for Earth’s slowing whirl on its axis are the braking action of tides, snow or the lack of it at the polar ice caps, solar wind, space dust and magnetic storms, according to the U.S. Commerce Department’s National Institute of Standards and Technology, another timekeeper.

By contrast, a leap day, February 29, occurs once every four years because a complete turn around the sun — our year with all its seasons — takes about 365 days and six hours.

In 1970, an international agreement established two time scales: one based on the Earth’s rotation and another on highly accurate atomic clocks.

The U.S. Naval Observatory’s master clock is based on a system that now includes 50 atomic clocks, 36 based on the element cesium and 14 known as hydrogen masers.

With the Earth’s rotation gradually slowing, the periodic insertion of a leap second into the atomic time scaleis needed to keep the two systems within a second of each other.

(Reporting by Jim Wolf; Editing by Peter Cooney)

2009 has been delayed

jacob1207 — Sat, 27 Dec 2008 14:59:01 +0000

The 2009th year of the common era is going to be delayed and its predecessor is being extended. For real. But just by a second.

As reported by MSNBC, the extra second, which is required to keep the time in sync with the Earth’s rotation, was ordered by the International Earth Rotation and Reference Systems Service (yes, that’s a real thing—here’s their website). Said rotation can vary slightly due to various factors, like the planet’s liquid core sloshing around and the gravitational effects of other Solar System bodies.

Leap seconds are added periodically; the last was inserted into 2005. Wikipedia has, unsurprisingly, more information on them.