PARIS - Scientists say Saturday will stretch a second longer
than any other day this year. A team at the Paris Observatory is
adding a "leap second" just before midnight to make up for a
gradual slowdown in the Earth's rotation. Experts at the
International Earth Rotation and Reference System Service make
the adjustment when the planet's movement falls out of sync with
atomic clocks used to measure time. A second can be added or
removed as needed every six months, but it typically happens
only every 1.5 years. This week's change comes after nearly four
years without a leap second — the last one was at the end of
December 2008. Twenty-four extra seconds have been introduced
since the process started in 1972. There are normally 86,400
seconds in a day. Click here to report a typo or error