According to the issue of "Bulletin C" (number 30) which I just received, there'll be a positive leap second at the end of 31 December 2005—the first such leap second since 1999, which is quite a long time.
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 e-mail : firstname.lastname@example.org http://hpiers.obspm.fr/eop-pc Paris, 4 July 2005 Bulletin C 30 To authorities responsible for the measurement and distribution of time UTC TIME STEP on the 1st of January 2006 A positive leap second will be introduced at the end of December 2005. The sequence of dates of the UTC second markers will be: 2005 December 31, 23h 59m 59s 2005 December 31, 23h 59m 60s 2006 January 1, 0h 0m 0s The difference between UTC and the International Atomic Time TAI is: from 1999 January 1, 0h UTC, to 2006 January 1 0h UTC : UTC-TAI = - 32s from 2006 January 1, 0h UTC, until further notice : UTC-TAI = - 33s 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