INTERNATIONAL EARTH ROTATION SERVICE (IERS)
SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE

BUREAU CENTRAL DE L'IERS
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 : iers@obspm.fr

Paris, 13 January 2000


Bulletin C 19

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 June 2000.
The difference between UTC and the International Atomic Time TAI is :

from 1999 January 1, 0h UTC, until further notice : UTC-TAI = - 32 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
Central Bureau of IERS