diff options
Diffstat (limited to 'leapseconds')
| -rw-r--r-- | leapseconds | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/leapseconds b/leapseconds new file mode 100644 index 0000000..ce150bf --- /dev/null +++ b/leapseconds @@ -0,0 +1,79 @@ +# Allowance for leap seconds added to each time zone file. + +# This file is in the public domain. + +# This file is generated automatically from the data in the public-domain +# NIST/IERS format leap-seconds.list file, which can be copied from +# <https://hpiers.obspm.fr/iers/bul/bulc/ntp/leap-seconds.list> +# or, in a variant with different comments, from +# <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>. +# For more about leap-seconds.list, please see +# The NTP Timescale and Leap Seconds +# <https://www.eecis.udel.edu/~mills/leap.html>. + +# The rules for leap seconds are specified in Annex 1 (Time scales) of: +# Standard-frequency and time-signal emissions. +# International Telecommunication Union - Radiocommunication Sector +# (ITU-R) Recommendation TF.460-6 (02/2002) +# <https://www.itu.int/rec/R-REC-TF.460-6-200202-I/>. +# The International Earth Rotation and Reference Systems Service (IERS) +# periodically uses leap seconds to keep UTC to within 0.9 s of UT1 +# (a proxy for Earth's angle in space as measured by astronomers) +# and publishes leap second data in a copyrighted file +# <https://hpiers.obspm.fr/iers/bul/bulc/Leap_Second.dat>. +# See: Levine J. Coordinated Universal Time and the leap second. +# URSI Radio Sci Bull. 2016;89(4):30-6. doi:10.23919/URSIRSB.2016.7909995 +# <https://ieeexplore.ieee.org/document/7909995>. + +# There were no leap seconds before 1972, as no official mechanism +# accounted for the discrepancy between atomic time (TAI) and the earth's +# rotation. The first ("1 Jan 1972") data line in leap-seconds.list +# does not denote a leap second; it denotes the start of the current definition +# of UTC. + +# All leap-seconds are Stationary (S) at the given UTC time. +# The correction (+ or -) is made at the given time, so in the unlikely +# event of a negative leap second, a line would look like this: +# Leap YEAR MON DAY 23:59:59 - S +# Typical lines look like this: +# Leap YEAR MON DAY 23:59:60 + S +Leap 1972 Jun 30 23:59:60 + S +Leap 1972 Dec 31 23:59:60 + S +Leap 1973 Dec 31 23:59:60 + S +Leap 1974 Dec 31 23:59:60 + S +Leap 1975 Dec 31 23:59:60 + S +Leap 1976 Dec 31 23:59:60 + S +Leap 1977 Dec 31 23:59:60 + S +Leap 1978 Dec 31 23:59:60 + S +Leap 1979 Dec 31 23:59:60 + S +Leap 1981 Jun 30 23:59:60 + S +Leap 1982 Jun 30 23:59:60 + S +Leap 1983 Jun 30 23:59:60 + S +Leap 1985 Jun 30 23:59:60 + S +Leap 1987 Dec 31 23:59:60 + S +Leap 1989 Dec 31 23:59:60 + S +Leap 1990 Dec 31 23:59:60 + S +Leap 1992 Jun 30 23:59:60 + S +Leap 1993 Jun 30 23:59:60 + S +Leap 1994 Jun 30 23:59:60 + S +Leap 1995 Dec 31 23:59:60 + S +Leap 1997 Jun 30 23:59:60 + S +Leap 1998 Dec 31 23:59:60 + S +Leap 2005 Dec 31 23:59:60 + S +Leap 2008 Dec 31 23:59:60 + S +Leap 2012 Jun 30 23:59:60 + S +Leap 2015 Jun 30 23:59:60 + S +Leap 2016 Dec 31 23:59:60 + S + +# UTC timestamp when this leap second list expires. +# Any additional leap seconds will come after this. +# This Expires line is commented out for now, +# so that pre-2020a zic implementations do not reject this file. +#Expires 2024 Dec 28 00:00:00 + +# POSIX timestamps for the data in this file: +#updated 1704708379 (2024-01-08 10:06:19 UTC) +#expires 1735344000 (2024-12-28 00:00:00 UTC) + +# Updated through IERS Bulletin C (https://hpiers.obspm.fr/iers/bul/bulc/bulletinc.dat) +# File expires on 28 December 2024 |