leapseconds revision 233445
1# <pre>
2# @(#)leapseconds	8.13
3# This file is in the public domain, so clarified as of
4# 2009-05-17 by Arthur David Olson.
5
6# Allowance for leapseconds added to each timezone file.
7
8# The International Earth Rotation Service periodically uses leap seconds
9# to keep UTC to within 0.9 s of UT1
10# (which measures the true angular orientation of the earth in space); see
11# Terry J Quinn, The BIPM and the accurate measure of time,
12# Proc IEEE 79, 7 (July 1991), 894-905.
13# There were no leap seconds before 1972, because the official mechanism
14# accounting for the discrepancy between atomic time and the earth's rotation
15# did not exist until the early 1970s.
16
17# The correction (+ or -) is made at the given time, so lines
18# will typically look like:
19#	Leap	YEAR	MON	DAY	23:59:60	+	R/S
20# or
21#	Leap	YEAR	MON	DAY	23:59:59	-	R/S
22
23# If the leapsecond is Rolling (R) the given time is local time
24# If the leapsecond is Stationary (S) the given time is UTC
25
26# Leap	YEAR	MONTH	DAY	HH:MM:SS	CORR	R/S
27Leap	1972	Jun	30	23:59:60	+	S
28Leap	1972	Dec	31	23:59:60	+	S
29Leap	1973	Dec	31	23:59:60	+	S
30Leap	1974	Dec	31	23:59:60	+	S
31Leap	1975	Dec	31	23:59:60	+	S
32Leap	1976	Dec	31	23:59:60	+	S
33Leap	1977	Dec	31	23:59:60	+	S
34Leap	1978	Dec	31	23:59:60	+	S
35Leap	1979	Dec	31	23:59:60	+	S
36Leap	1981	Jun	30	23:59:60	+	S
37Leap	1982	Jun	30	23:59:60	+	S
38Leap	1983	Jun	30	23:59:60	+	S
39Leap	1985	Jun	30	23:59:60	+	S
40Leap	1987	Dec	31	23:59:60	+	S
41Leap	1989	Dec	31	23:59:60	+	S
42Leap	1990	Dec	31	23:59:60	+	S
43Leap	1992	Jun	30	23:59:60	+	S
44Leap	1993	Jun	30	23:59:60	+	S
45Leap	1994	Jun	30	23:59:60	+	S
46Leap	1995	Dec	31	23:59:60	+	S
47Leap	1997	Jun	30	23:59:60	+	S
48Leap	1998	Dec	31	23:59:60	+	S
49Leap	2005	Dec	31	23:59:60	+	S
50Leap	2008	Dec	31	23:59:60	+	S
51Leap	2012	Jun	30	23:59:60	+	S
52
53# INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS)
54#
55# SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE ET DES SYSTEMES DE REFERENCE
56#
57#
58# SERVICE DE LA ROTATION TERRESTRE
59# OBSERVATOIRE DE PARIS
60# 61, Av. de l'Observatoire 75014 PARIS (France)
61# Tel.      : 33 (0) 1 40 51 22 26
62# FAX       : 33 (0) 1 40 51 22 91
63# e-mail    : (E-Mail Removed)
64# http://hpiers.obspm.fr/eop-pc
65#
66# Paris, 5 January 2012
67#
68#
69# Bulletin C 43
70#
71# To authorities responsible
72# for the measurement and
73# distribution of time
74#
75#
76# UTC TIME STEP
77# on the 1st of July 2012
78#
79#
80# A positive leap second will be introduced at the end of June 2012.
81# The sequence of dates of the UTC second markers will be:		
82# 		
83#                          2012 June 30,     23h 59m 59s
84#                          2012 June 30,     23h 59m 60s
85#                          2012 July  1,      0h  0m  0s
86#
87# The difference between UTC and the International Atomic Time TAI is:
88#
89# from 2009 January 1, 0h UTC, to 2012 July 1  0h UTC  : UTC-TAI = - 34s
90# from 2012 July 1,    0h UTC, until further notice    : UTC-TAI = - 35s
91#
92# Leap seconds can be introduced in UTC at the end of the months of December
93# or June, depending on the evolution of UT1-TAI. Bulletin C is mailed every
94# six months, either to announce a time step in UTC or to confirm that there
95# will be no time step at the next possible date.
96#
97#
98# Daniel GAMBIS
99# Head		
100# Earth Orientation Center of IERS
101# Observatoire de Paris, France
102