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
FAX       : 33 (0) 1 40 51 22 91
Internet  : services.iers@obspm.fr


Paris, 28 June 2007




Bulletin C 34


To authorities responsible
for the measurement and
distribution of time






INFORMATION ON UTC - TAI




NO positive leap second will be introduced at the end of December 2007.
The difference between Coordinated Universal Time UTC and the
International Atomic Time TAI is :


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


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
Director
Earth Orientation Center of IERS
Observatoire de Paris, France