One Second at a Time
Which is to say that June 30th 2012 was 86,401 seconds long. An additional leap second was added to account for the slowing of Earth’s rotation, and to ensure that our atomic clock and the solar Year are in synch. Fortunately, theAbysmal Calendar allows for such adjustments without throwing off the perpetual year (although a leap second is hardly as disruptive as daylight savings). Any adjustments to the calendar year, whether leap seconds or days or what have you, can be added to the New Year’s Day (equivalent to December 21st), without changing the other 364 days of the year.
from the cbc
June 30, 2012 will be exactly one second longer than any other day this year, according to the world’s timekeepers.
Horologists will be adding one “leap second” to Coordinated Universal Time (UTC) this weekend to compensate for the very gradual and unpredictable slowing down of our planet.
Basically, there are two main standards for measuring time on earth: solar time, based on the rotation of the earth, and International Atomic Time, which relies on the pulsation of atoms to measure time with near-perfect accuracy.
The earth takes just over 86,400 seconds for a full 360-degree revolution, but the gravitational pull of ocean tides, the sun and the moon all affect its rotation ever so slightly.
This has led to a creeping discrepancy between the two times, which the International Earth Rotation and Reference Systems Service (IERS) decided to start fixing in 1971 with the introduction of leap seconds. A total of 24 leap seconds have been added to the clock since.
These leap seconds must be inserted every 1 to 2 years to avoid solar time and atomic time from spreading too far apart, according to the IERS.
However, due to an unusual temporary acceleration of the Earth, no leap seconds were needed between 1998 and 2005. The last leap second occurred at the end of December in 2008.
This weekend’s leap second will effectively make the last minute of June 61 seconds, instead of the standard 60 – meaning that you have one extra second to enjoy this Canada Day long weekend.
174 Days to Dec 21st 2012