[IGSMAIL-5789]: Leap Second Announcement (IERS Bulletin C36)

[Jim.Ray]

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IGS Electronic Mail      07 Jul 06:14:22 PDT 2008      Message Number 5789
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Author: Jim Ray (forward IERS Bulletin C36)

Users should consider updating their leap second
control files for the next one on 31 December 2008.
After that epoch, the following will apply:

   TAI - UTC      = 34 s   (after 31 Dec 2008)
   GPS Time - UTC = 15 s   (modulo seconds, after 31 Dec 2008)


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      INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS)

SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE ET DES SYSTEMES DE REFERENCE

SERVICE DE LA ROTATION TERRESTRE
OBSERVATOIRE DE PARIS
61, Av. de l'Observatoire 75014 PARIS (France)
Tel.      : 33 (0) 1 40 51 22 26
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e-mail    : services.iers at obspm.fr
http://hpiers.obspm.fr/eop-pc

                                               Paris, 4 July 2008

                                               Bulletin C 36

                                               To authorities responsible
					      for the measurement and
					      distribution of time


                                    UTC TIME STEP
                             on the 1st of January 2009


  A positive leap second will be introduced at the end of December 2008.
  The sequence of dates of the UTC second markers will be:

                           2008 December 31,     23h 59m 59s
                           2008 December 31,     23h 59m 60s
                           2009 January   1,      0h  0m  0s

  The difference between UTC and the International Atomic Time TAI is:

   from 2006 January 1, 0h UTC, to 2009 January 1  0h UTC  : UTC-TAI = - 33s
   from 2009 January 1, 0h UTC, until further notice       : UTC-TAI = - 34s

  Leap seconds can be introduced in UTC at the end of the months of December
  or June, depending on the evolution of UT1-TAI. Bulletin C is mailed every
  six months, either to announce a time step in UTC or to confirm that there
  will be no time step at the next possible date.



                                               Daniel GAMBIS
                                               Head
                                               Earth Orientation Center of IERS
					      Observatoire de Paris, France