leapseconds (3286B)
1 # <pre> 2 # This file is in the public domain, so clarified as of 3 # 2009-05-17 by Arthur David Olson. 4 5 # Allowance for leapseconds added to each timezone file. 6 7 # The International Earth Rotation Service periodically uses leap seconds 8 # to keep UTC to within 0.9 s of UT1 9 # (which measures the true angular orientation of the earth in space); see 10 # Terry J Quinn, The BIPM and the accurate measure of time, 11 # Proc IEEE 79, 7 (July 1991), 894-905. 12 # There were no leap seconds before 1972, because the official mechanism 13 # accounting for the discrepancy between atomic time and the earth's rotation 14 # did not exist until the early 1970s. 15 16 # The correction (+ or -) is made at the given time, so lines 17 # will typically look like: 18 # Leap YEAR MON DAY 23:59:60 + R/S 19 # or 20 # Leap YEAR MON DAY 23:59:59 - R/S 21 22 # If the leapsecond is Rolling (R) the given time is local time 23 # If the leapsecond is Stationary (S) the given time is UTC 24 25 # Leap YEAR MONTH DAY HH:MM:SS CORR R/S 26 Leap 1972 Jun 30 23:59:60 + S 27 Leap 1972 Dec 31 23:59:60 + S 28 Leap 1973 Dec 31 23:59:60 + S 29 Leap 1974 Dec 31 23:59:60 + S 30 Leap 1975 Dec 31 23:59:60 + S 31 Leap 1976 Dec 31 23:59:60 + S 32 Leap 1977 Dec 31 23:59:60 + S 33 Leap 1978 Dec 31 23:59:60 + S 34 Leap 1979 Dec 31 23:59:60 + S 35 Leap 1981 Jun 30 23:59:60 + S 36 Leap 1982 Jun 30 23:59:60 + S 37 Leap 1983 Jun 30 23:59:60 + S 38 Leap 1985 Jun 30 23:59:60 + S 39 Leap 1987 Dec 31 23:59:60 + S 40 Leap 1989 Dec 31 23:59:60 + S 41 Leap 1990 Dec 31 23:59:60 + S 42 Leap 1992 Jun 30 23:59:60 + S 43 Leap 1993 Jun 30 23:59:60 + S 44 Leap 1994 Jun 30 23:59:60 + S 45 Leap 1995 Dec 31 23:59:60 + S 46 Leap 1997 Jun 30 23:59:60 + S 47 Leap 1998 Dec 31 23:59:60 + S 48 Leap 2005 Dec 31 23:59:60 + S 49 Leap 2008 Dec 31 23:59:60 + S 50 Leap 2012 Jun 30 23:59:60 + S 51 52 # INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS) 53 # 54 # SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE ET DES SYSTEMES DE REFERENCE 55 # 56 # 57 # SERVICE DE LA ROTATION TERRESTRE 58 # OBSERVATOIRE DE PARIS 59 # 61, Av. de l'Observatoire 75014 PARIS (France) 60 # Tel. : 33 (0) 1 40 51 22 26 61 # FAX : 33 (0) 1 40 51 22 91 62 # e-mail : (E-Mail Removed) 63 # http://hpiers.obspm.fr/eop-pc 64 # 65 # Paris, 5 January 2012 66 # 67 # 68 # Bulletin C 43 69 # 70 # To authorities responsible 71 # for the measurement and 72 # distribution of time 73 # 74 # 75 # UTC TIME STEP 76 # on the 1st of July 2012 77 # 78 # 79 # A positive leap second will be introduced at the end of June 2012. 80 # The sequence of dates of the UTC second markers will be: 81 # 82 # 2012 June 30, 23h 59m 59s 83 # 2012 June 30, 23h 59m 60s 84 # 2012 July 1, 0h 0m 0s 85 # 86 # The difference between UTC and the International Atomic Time TAI is: 87 # 88 # from 2009 January 1, 0h UTC, to 2012 July 1 0h UTC : UTC-TAI = - 34s 89 # from 2012 July 1, 0h UTC, until further notice : UTC-TAI = - 35s 90 # 91 # Leap seconds can be introduced in UTC at the end of the months of December 92 # or June, depending on the evolution of UT1-TAI. Bulletin C is mailed every 93 # six months, either to announce a time step in UTC or to confirm that there 94 # will be no time step at the next possible date. 95 # 96 # 97 # Daniel GAMBIS 98 # Head 99 # Earth Orientation Center of IERS 100 # Observatoire de Paris, France