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1 # @(#)leapseconds 8.1 |
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2 |
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3 # Allowance for leapseconds added to each timezone file. |
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4 |
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5 # The International Earth Rotation Service periodically uses leap seconds |
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6 # to keep UTC to within 0.9 s of UT1 |
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7 # (which measures the true angular orientation of the earth in space); see |
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8 # Terry J Quinn, The BIPM and the accurate measure of time, |
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9 # Proc IEEE 79, 7 (July 1991), 894-905. |
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10 # There were no leap seconds before 1972, because the official mechanism |
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11 # accounting for the discrepancy between atomic time and the earth's rotation |
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12 # did not exist until the early 1970s. |
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13 |
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14 # The correction (+ or -) is made at the given time, so lines |
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15 # will typically look like: |
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16 # Leap YEAR MON DAY 23:59:60 + R/S |
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17 # or |
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18 # Leap YEAR MON DAY 23:59:59 - R/S |
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19 |
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20 # If the leapsecond is Rolling (R) the given time is local time |
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21 # If the leapsecond is Stationary (S) the given time is UTC |
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22 |
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23 # Leap YEAR MONTH DAY HH:MM:SS CORR R/S |
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24 Leap 1972 Jun 30 23:59:60 + S |
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25 Leap 1972 Dec 31 23:59:60 + S |
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26 Leap 1973 Dec 31 23:59:60 + S |
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27 Leap 1974 Dec 31 23:59:60 + S |
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28 Leap 1975 Dec 31 23:59:60 + S |
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29 Leap 1976 Dec 31 23:59:60 + S |
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30 Leap 1977 Dec 31 23:59:60 + S |
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31 Leap 1978 Dec 31 23:59:60 + S |
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32 Leap 1979 Dec 31 23:59:60 + S |
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33 Leap 1981 Jun 30 23:59:60 + S |
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34 Leap 1982 Jun 30 23:59:60 + S |
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35 Leap 1983 Jun 30 23:59:60 + S |
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36 Leap 1985 Jun 30 23:59:60 + S |
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37 Leap 1987 Dec 31 23:59:60 + S |
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38 Leap 1989 Dec 31 23:59:60 + S |
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39 Leap 1990 Dec 31 23:59:60 + S |
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40 Leap 1992 Jun 30 23:59:60 + S |
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41 Leap 1993 Jun 30 23:59:60 + S |
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42 Leap 1994 Jun 30 23:59:60 + S |
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43 Leap 1995 Dec 31 23:59:60 + S |
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44 Leap 1997 Jun 30 23:59:60 + S |
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45 Leap 1998 Dec 31 23:59:60 + S |
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46 Leap 2005 Dec 31 23:59:60 + S |
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47 |
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48 # INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS) |
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49 # |
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50 # SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE ET DES SYSTEMES DE REFERENCE |
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51 # |
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52 # SERVICE DE LA ROTATION TERRESTRE |
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53 # OBSERVATOIRE DE PARIS |
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54 # 61, Av. de l'Observatoire 75014 PARIS (France) |
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55 # Tel. : 33 (0) 1 40 51 22 26 |
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56 # FAX : 33 (0) 1 40 51 22 91 |
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57 # ... |
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58 # http://hpiers.obspm.fr/eop-pc |
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59 # |
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60 # Paris, 4 July 2005 |
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61 # |
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62 # Bulletin C 30 |
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63 # |
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64 # To authorities responsible |
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65 # for the measurement and |
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66 # distribution of time |
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67 # |
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68 # |
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69 # UTC TIME STEP |
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70 # on the 1st of January 2006 |
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71 # |
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72 # A positive leap second will be introduced at the end of December 2005. |
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73 # The sequence of dates of the UTC second markers will be: |
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74 # |
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75 # 2005 December 31, 23h 59m 59s |
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76 # 2005 December 31, 23h 59m 60s |
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77 # 2006 January 1, 0h 0m 0s |
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78 # |
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79 # The difference between UTC and the International Atomic Time TAI is: |
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80 # |
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81 # from 1999 January 1, 0h UTC, to 2006 January 1 0h UTC : UTC-TAI = - 32s |
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82 # from 2006 January 1, 0h UTC, until further notice : UTC-TAI = - 33s |
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83 # |
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84 # Leap seconds can be introduced in UtC at the end of the months of December |
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85 # or June, depending on the evolution of UT1-TAI. Bulletin C is mailed every |
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86 # six months, either to announce a time step in UTC or to confirm that there |
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87 # will be no time step at the next possible date. |
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88 # |
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89 # Daniel GAMBIS |
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90 # Head |
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91 # Earth Orientation Center of IERS |
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92 # Observatoire de Paris, France |