e List of Leap Seconds -- from Harry J. Smith

List of Leap Seconds



Here is the complete list of leap seconds:

  • # 0 delta=10 Dec 31, 1971 good for 0.5 years (UTC redefined = TAI - 10 seconds)
  • # 1 delta=11 Jun 30, 1972 good for 0.5 years (First true leap second)
  • # 2 delta=12 Dec 31, 1972 good for 1.0 years
  • # 3 delta=13 Dec 31, 1973 good for 1.0 years
  • # 4 delta=14 Dec 31, 1974 good for 1.0 years
  • # 5 delta=15 Dec 31, 1975 good for 1.0 years
  • # 6 delta=16 Dec 31, 1976 good for 1.0 years
  • # 7 delta=17 Dec 31, 1977 good for 1.0 years
  • # 8 delta=18 Dec 31, 1978 good for 1.0 years
  • # 9 delta=19 Dec 31, 1979 good for 1.5 years
  • #10 delta=20 Jun 30, 1981 good for 1.0 years
  • #11 delta=21 Jun 30, 1982 good for 1.0 years
  • #12 delta=22 Jun 30, 1983 good for 2.0 years
  • #13 delta=23 Jun 30, 1985 good for 2.5 years
  • #14 delta=24 Dec 31, 1987 good for 2.0 years
  • #15 delta=25 Dec 31, 1989 good for 1.0 years
  • #16 delta=26 Dec 31, 1990 good for 1.5 years
  • #17 delta=27 Jun 30, 1992 good for 1.0 years
  • #18 delta=28 Jun 30, 1993 good for 1.0 years
  • #19 delta=29 Jun 30, 1994 good for 1.5 years
  • #20 delta=30 Dec 31, 1995 good for 1.5 years
  • #21 delta=31 Jun 30, 1997 good for 1.5 years
  • #22 delta=32 Dec 31, 1998 good for 7.0 years
  • #23 delta=33 Dec 31, 2005 good for 3.0 years
  • #24 delta=34 Dec 31, 2008 good for ?.? years

    Leap seconds did not exist before the year 1972. At the start of January 1, 1972, UTC was redefined to be equal to UT1 and equal to TAI minus 10 seconds. The first true leap second was inserted at the end of June 30, 1972 when UTC was changed to TAI - 11 seconds.

    -Harry

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    This page accessed times since Feb 5, 2006.
    Page created by: hjsmithh@sbcglobal.net
    Changes last made on Sunday, 07-Dec-08 17:08:49 PST

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