2008 Will Be Just a Second Longer
On Dec. 31 this year, your day will be just a second longer.
Like the more well-known time adjustment, the leap year, a "leap second" is tacked on to clocks every so often to keep them correct.
Earth's trip around the sun - our year with all its seasons - is about 365.2422 days long, which we round to 365 to keep things simpler. But every four years, we add 0.2422 x 4 days (that's about one day) at the end of the month of February (extending it from 28 to 29 days) to fix the calendar... http://news.yahoo.com/s/livescience/2008willbejustasecondlonger