This year, 2005, will be one second longer than any year since 1998. Nature reports that a leap second is being added to account for changes in the earth's rotation.
Leap seconds have been added since the 1970s when scientists noticed that atomic clocks and the astronomical clock of the earth's rotation do not always match up. Markus Kuhn of Cambridge University said that the gravitational pull of the sun and moon can change the rotation by causing shifts in the earth's core, and major earthquakes can do the same thing.
A total of 32 seconds have already been added over the decades, making the year just over half a minute longer.
The leap seconds are different from the days added every four years because the earth actually takes about 365 1/4 days to move around the sun.
Kuhn said that most computers will not have trouble dealing with the extra second, which will be added sometime in the final hours of Dec. 31.
Asked how he would spend the extra time, Kuhn told Nature, "I might do a very geeky thing and watch how my computer behaves."
Copyright 2005 by United Press International
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