| leapseconds (345670) | leapseconds (352354) |
|---|---|
| 1# Allowance for leap seconds added to each time zone file. 2 3# This file is in the public domain. 4 5# This file is generated automatically from the data in the public-domain | 1# Allowance for leap seconds added to each time zone file. 2 3# This file is in the public domain. 4 5# This file is generated automatically from the data in the public-domain |
| 6# leap-seconds.list file, which can be copied from | 6# NIST format leap-seconds.list file, which can be copied from |
| 7# <ftp://ftp.nist.gov/pub/time/leap-seconds.list> | 7# <ftp://ftp.nist.gov/pub/time/leap-seconds.list> |
| 8# or 9# or <ftp://tycho.usno.navy.mil/pub/ntp/leap-seconds.list>. | 8# or <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>. |
| 10# For more about leap-seconds.list, please see 11# The NTP Timescale and Leap Seconds 12# <https://www.eecis.udel.edu/~mills/leap.html>. 13 | 9# For more about leap-seconds.list, please see 10# The NTP Timescale and Leap Seconds 11# <https://www.eecis.udel.edu/~mills/leap.html>. 12 |
| 14# The International Earth Rotation and Reference Systems Service | 13# The rules for leap seconds are specified in Annex 1 (Time scales) of: 14# Standard-frequency and time-signal emissions. 15# International Telecommunication Union - Radiocommunication Sector 16# (ITU-R) Recommendation TF.460-6 (02/2002) 17# <https://www.itu.int/rec/R-REC-TF.460-6-200202-I/>. 18# The International Earth Rotation and Reference Systems Service (IERS) |
| 15# periodically uses leap seconds to keep UTC to within 0.9 s of UT1 | 19# periodically uses leap seconds to keep UTC to within 0.9 s of UT1 |
| 16# (which measures the true angular orientation of the earth in space) | 20# (a proxy for Earth's angle in space as measured by astronomers) |
| 17# and publishes leap second data in a copyrighted file 18# <https://hpiers.obspm.fr/iers/bul/bulc/Leap_Second.dat>. 19# See: Levine J. Coordinated Universal Time and the leap second. 20# URSI Radio Sci Bull. 2016;89(4):30-6. doi:10.23919/URSIRSB.2016.7909995 21# <https://ieeexplore.ieee.org/document/7909995>. 22 | 21# and publishes leap second data in a copyrighted file 22# <https://hpiers.obspm.fr/iers/bul/bulc/Leap_Second.dat>. 23# See: Levine J. Coordinated Universal Time and the leap second. 24# URSI Radio Sci Bull. 2016;89(4):30-6. doi:10.23919/URSIRSB.2016.7909995 25# <https://ieeexplore.ieee.org/document/7909995>. 26 |
| 23# There were no leap seconds before 1972, because the official mechanism 24# accounting for the discrepancy between atomic time and the earth's rotation 25# did not exist. The first ("1 Jan 1972") data line in leap-seconds.list | 27# There were no leap seconds before 1972, as no official mechanism 28# accounted for the discrepancy between atomic time (TAI) and the earth's 29# rotation. The first ("1 Jan 1972") data line in leap-seconds.list |
| 26# does not denote a leap second; it denotes the start of the current definition 27# of UTC. 28 | 30# does not denote a leap second; it denotes the start of the current definition 31# of UTC. 32 |
| 29# The correction (+ or -) is made at the given time, so lines 30# will typically look like: 31# Leap YEAR MON DAY 23:59:60 + R/S 32# or 33# Leap YEAR MON DAY 23:59:59 - R/S 34 35# If the leap second is Rolling (R) the given time is local time (unused here). | 33# All leap-seconds are Stationary (S) at the given UTC time. 34# The correction (+ or -) is made at the given time, so in the unlikely 35# event of a negative leap second, a line would look like this: 36# Leap YEAR MON DAY 23:59:59 - S 37# Typical lines look like this: 38# Leap YEAR MON DAY 23:59:60 + S |
| 36Leap 1972 Jun 30 23:59:60 + S 37Leap 1972 Dec 31 23:59:60 + S 38Leap 1973 Dec 31 23:59:60 + S 39Leap 1974 Dec 31 23:59:60 + S 40Leap 1975 Dec 31 23:59:60 + S 41Leap 1976 Dec 31 23:59:60 + S 42Leap 1977 Dec 31 23:59:60 + S 43Leap 1978 Dec 31 23:59:60 + S --- 13 unchanged lines hidden (view full) --- 57Leap 1998 Dec 31 23:59:60 + S 58Leap 2005 Dec 31 23:59:60 + S 59Leap 2008 Dec 31 23:59:60 + S 60Leap 2012 Jun 30 23:59:60 + S 61Leap 2015 Jun 30 23:59:60 + S 62Leap 2016 Dec 31 23:59:60 + S 63 64# POSIX timestamps for the data in this file: | 39Leap 1972 Jun 30 23:59:60 + S 40Leap 1972 Dec 31 23:59:60 + S 41Leap 1973 Dec 31 23:59:60 + S 42Leap 1974 Dec 31 23:59:60 + S 43Leap 1975 Dec 31 23:59:60 + S 44Leap 1976 Dec 31 23:59:60 + S 45Leap 1977 Dec 31 23:59:60 + S 46Leap 1978 Dec 31 23:59:60 + S --- 13 unchanged lines hidden (view full) --- 60Leap 1998 Dec 31 23:59:60 + S 61Leap 2005 Dec 31 23:59:60 + S 62Leap 2008 Dec 31 23:59:60 + S 63Leap 2012 Jun 30 23:59:60 + S 64Leap 2015 Jun 30 23:59:60 + S 65Leap 2016 Dec 31 23:59:60 + S 66 67# POSIX timestamps for the data in this file: |
| 65#updated 1467936000 66#expires 1577491200 | 68#updated 1467936000 (2016-07-08 00:00:00 UTC) 69#expires 1593302400 (2020-06-28 00:00:00 UTC) |
| 67 | 70 |
| 68# Updated through IERS Bulletin C57 69# File expires on: 28 December 2019 | 71# Updated through IERS Bulletin C58 72# File expires on: 28 June 2020 |