Earth and Moon to scale. Originally uploaded by Bluedharma

On December 31, 2008 an extra second will be added to the world’s clocks at 23 hours, 59 minutes, and 59 seconds Coordinated Universal Time (UTC).

This is also called a ‘leap second’ (similar to leap year) and is the 24th leap second to have ever been added to the UTC since 1972.

Quick Astronomy Lesson via
Historically, time was based on the mean rotation of Earth relative to celestial bodies and the second was defined in this reference frame. However, the invention of atomic clocks defined a much more precise “atomic time” scale and a second that is independent of Earth’s rotation. In 1970, an international agreement established two time scales: one based on Earth’s rotation and one based on atomic time. The problem is that Earth’s rotation is gradually slowing down, which necessitates the periodic insertion of a “leap second” into the atomic time scale to keep the two within 1 second of each other. The International Earth Rotation and Reference Systems Service (IERS) monitors the difference in the two time scales and calls for leap seconds to be inserted or removed when necessary. Since 1972, leap seconds have been added at intervals varying from 6 months to 7 years, with the last being inserted December 31, 2005.

Don’t worry, our infamous new years count down will not be disrupted by this ‘leap second’. Since the second is being added on 11:59:59 PM UTC, it translates to 5:59:59 PM Winnipeg time.

Unfortunately, for people living in UTC Countries (UK, Spain, Ireland…) their countdown will be 5 – 4 – 3 – 2 – 1 – 1 – HAPPY NEW YEAR!!!