% (last updated 2018-12-14)
% Delta-T 1620-1972
% delta-T = ET - UT for the years 1620 - 1972
% ET-UT, s
%
% Year +0.0 +1.0 +2.0 +3.0 +4.0
% ----------------------------------------------------
% 1620 +124 +119 +115 +110 +106
% 1625 +102 +98 +95 +91 +88
% 1630 +85 +82 +79 +77 +74
% 1635 +72 +70 +67 +65 +63
% 1640 +62 +60 +58 +57 +55
% 1645 +54 +53 +51 +50 +49
% 1650 +48 +47 +46 +45 +44
% 1655 +43 +42 +41 +40 +38
% 1660 +37 +36 +35 +34 +33
% 1665 +32 +31 +30 +28 +27
% 1670 +26 +25 +24 +23 +22
% 1675 +21 +20 +19 +18 +17
% 1680 +16 +15 +14 +14 +13
% 1685 +12 +12 +11 +11 +10
% 1690 +10 +9 +9 +9 +9
% 1695 +9 +9 +9 +9 +9
% 1700 +10 +9 +9 +9 +9
% 1705 +9 +9 +9 +10 +10
% 1710 +10 +10 +10 +10 +10
% 1715 +10 +10 +11 +11 +11
% 1720 +11 +11 +11 +11 +11
% 1725 +11 +11 +11 +11 +11
% 1730 +11 +11 +11 +11 +12
% 1735 +12 +12 +12 +12 +12
% 1740 +12 +12 +12 +12 +13
% 1745 +13 +13 +13 +13 +13
% 1750 +13 +14 +14 +14 +14
% 1755 +14 +14 +14 +15 +15
% 1760 +15 +15 +15 +15 +15
% 1765 +16 +16 +16 +16 +16
% 1770 +16 +16 +16 +16 +16
% 1775 +17 +17 +17 +17 +17
% 1780 +17 +17 +17 +17 +17
% 1785 +17 +17 +17 +17 +17
% 1790 +17 +17 +16 +16 +16
% 1795 +16 +15 +15 +14 +14
% 1800 +13.7 +13.4 +13.1 +12.9 +12.7
% 1805 +12.6 +12.5 +12.5 +12.5 +12.5
% 1810 +12.5 +12.5 +12.5 +12.5 +12.5
% 1815 +12.5 +12.5 +12.4 +12.3 +12.2
% 1820 +12.0 +11.7 +11.4 +11.1 +10.6
% 1825 +10.2 +9.6 +9.1 +8.6 +8.0
% 1830 +7.5 +7.0 +6.6 +6.3 +6.0
% 1835 +5.8 +5.7 +5.6 +5.6 +5.6
% 1840 +5.7 +5.8 +5.9 +6.1 +6.2
% 1845 +6.3 +6.5 +6.6 +6.8 +6.9
% 1850 +7.1 +7.2 +7.3 +7.4 +7.5
% 1855 +7.6 +7.7 +7.7 +7.8 +7.8
% 1860 +7.88 +7.82 +7.54 +6.97 +6.40
% 1865 +6.02 +5.41 +4.10 +2.92 +1.81
% 1870 +1.61 +0.10 -1.02 -1.28 -2.69
% 1875 -3.24 -3.64 -4.54 -4.71 -5.11
% 1880 -5.40 -5.42 -5.20 -5.46 -5.46
% 1885 -5.79 -5.63 -5.64 -5.80 -5.66
% 1890 -5.87 -6.01 -6.19 -6.64 -6.44
% 1895 -6.47 -6.09 -5.76 -4.66 -3.74
% 1900 -2.72 -1.54 -0.02 +1.24 +2.64
% 1905 +3.86 +5.37 +6.14 +7.75 +9.13
% 1910 +10.46 +11.53 +13.36 +14.65 +16.01
% 1915 +17.20 +18.24 +19.06 +20.25 +20.95
% 1920 +21.16 +22.25 +22.41 +23.03 +23.49
% 1925 +23.62 +23.86 +24.49 +24.34 +24.08
% 1930 +24.02 +24.00 +23.87 +23.95 +23.86
% 1935 +23.93 +23.73 +23.92 +23.96 +24.02
% 1940 +24.33 +24.83 +25.30 +25.70 +26.24
% 1945 +26.77 +27.28 +27.78 +28.25 +28.71
% 1950 +29.15 +29.57 +29.97 +30.36 +30.72
% 1955 +31.07 +31.35 +31.68 +32.18 +32.68
% 1960 +33.15 +33.59 +34.00 +34.47 +35.03
% 1965 +35.73 +36.54 +37.43 +38.29 +39.20
% 1970 +40.18 +41.17 +42.23
%1620年-1972年曆書時ET與世界時UT之間的關係
% ET = Ephemeris Time. Was used 1960-1983, and was replaced by TDT and TDB
% in 1984. For most purposes, ET up to 1983 Dec 31 and TDT from 1984
% Jan 1 can be regarded as a continuous time-scale.
% ET = 曆書時. 使用於1960年-1983年,1984年被TDT和TDB取代. 在大多數場合,直至1983年12月31日的ET
% 和始於1984年1月1日的TDT可以認爲是連續時間量.
% UT = Universal time. Defined by the Earth's rotation, formerly determined
% by astronomical observations but today GPS satellites are used
% instead. This time scale is slightly irregular. There are several
% different definitions of UT, but the difference between them is always
% less than about 0.03 s.
% UT = 世界時. 根據地球自轉定義, 起初根據天文觀測確定, 現在根據GPS衛星確定. 該時間量
% 輕微不規則. UT有幾種不同的定義, 它們之間的差別小於0.03s.