Gnuplot
Produced by GNUPLOT 5.4 patchlevel 3
-120
-100
-80
-60
-40
-20
0
20
1600
1650
1700
1750
1800
1850
1900
1950
2000
Difference from (proleptic) TT [s]
Besselian epoch [yr]
gnuplot_plot_1
gnuplot_plot_2
gnuplot_plot_3
gnuplot_plot_4
gnuplot_plot_5
gnuplot_plot_6
gnuplot_plot_7
gnuplot_plot_8
gnuplot_plot_9
gnuplot_plot_10
gnuplot_plot_11
gnuplot_plot_12
gnuplot_plot_13
gnuplot_plot_14
gnuplot_plot_15
gnuplot_plot_16
gnuplot_plot_17
gnuplot_plot_18
gnuplot_plot_19
gnuplot_plot_20
gnuplot_plot_21
gnuplot_plot_22
gnuplot_plot_23
gnuplot_plot_24
gnuplot_plot_25
data for Newcomb's Tables
TAI
1958-01-01
LORAN-C
1972-01-01
GPS
1980-01-06
BST
2006-01-01
1977-01-01
1991
proleptic TT
proleptic TCG
proleptic TCB
proleptic UT
Royal Greenwich Observatory (1676) => GMT begins
1712 February 30
UK almanac changes from GAT to GMT (1834)
UK railways adopt standard time (1840)
US/Canada railways adopt standard time (1883-11-18)
International Meridian Conference (1884-10)
(time and date according to the sun)
international use of Newcomb's Tables (1901)
UK adopts Gregorian calendar (1752)
secular acceleration of the moon (Halley 1693)
tidal friction (Kant 1754)
tidal friction (Laplace 1787)
Newton's Principia (1687)
trans-atlantic telegraph (1866)
seasonal variation of earth rotation (Stoyko 1937)
quartz crystal clock (1927)
Shortt free pendulum clock (1921)
radio broadcast time signals (1904)
UK Longitude Prize offered (1714)
UK Board of Longitude dissolved (1828)
IAU resolves to use ET starting in 1960 (1952)
Steve Allen https://www.ucolick.org/~sla/leapsecs/
Telescopic Era differences in Time Scales