Subject: [SLR-Mail] No. 1740: Reminder: Leap Second on 2008/12/31 23:59:60 From: Frank G. Lemoine > ******************************************************************************** SLR Electronic Mail 2008-12-24 02:23:00 UTC Message No. 1740 ******************************************************************************** Author: Frank G. Lemoine Subject: Reminder: Leap Second on 2008/12/31 23:59:60 Subject: Reminder: Leap Second on 2008/12/31 23:59:60 Subject: Reminder: Leap Second on 2008/12/31 23:59:60 Dear Colleagues- This is a reminder that a leap second has been scheduled for the end of the 2008 calendar year, as per IERS message Bulletin C, No 36 dated July 5, 2008 from Daniel Gambis. Sincerely, F. Lemoine NASA Goddard Space Flight Center ----------------------------------------------------------------------- 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 : services.iers@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 the IERS, Observatoire de Paris, France From: ”Frank G. Lemoine” ********************************************************************************