Sidereal Time Calculator For Any Date, Time and Longitude
Local Date
±
YMD (Neg=BC)
Local Time
HMS (00 to 24h)
Time Zone Difference
HM (00 to ±12h)
ΔT (Delta T)
±
HMS
Local Time
= UT
2459423.5
0.000000000000
+0.208333333333
+0.000000000000
Calendar Mode:
Julian
Gregorian
Longitude:
±
D M S (Neg=W)
-76.8233055556
Optional ΔT estimate = +72 = +00h 01m 12s
This program uses a cookie to store and remember the above interface settings between calls.
SIDEREAL TIME FOR GIVEN DATE, TIME AND LONGITUDE Local Date = 20210728 = 2021 Jul 28 [Wednesday] Gregorian JD00 = 2459423.5 = JD number for 00h TT of date Local Time = 00:00:00 = 0.000000000000 day T Zone Diff = +05:00 = +0.208333333333 day Delta T = +00:00:00 = +0.000000000000 day Full astronomical JD number = Sum of all given date/time elements above JD = 2459423.708333333333 = (JD00 + LTFrac + TZFrac + dTFrac) Date/Time TT Corresponding to Full JD 20210728 05:00:00.0 TT Longitude = -76° 49' 23.9" = -76.8233055556° (W) = -05h 07m 17.6s = -5.1215537037 h ================================================================= Local Mean Sidereal Time at Longitude -76.8233055556° (W) 20h 17m 04s = 20.2843632960 h 304° 15' 56" = 304.2654494401° Local True Sidereal Time at Longitude = -76.8233055556° (W) 20h 17m 03s = 20.2841171337 h 304° 15' 42" = 304.2617570051° Greenwich Mean Sidereal Time at Longitude 0.0° 01h 24m 21.301s = 1.4059169997 h 21° 05' 19.518" = 21.0887549957° Greenwich True Sidereal Time at Longitude 0.0° 01h 24m 20.415s = 1.4056708374 h 21° 05' 06.225" = 21.0850625607° ================================================================= Applied Auxiliary Computations Time Factors Corresponding to Full Astronomical JD T = 0.215707278120 Julian centuries reckoned from J2000.0 t = 0.021570727812 Julian millennia reckoned from J2000.0 Nutations (IAU 2000B Series) -14.488" = -0.0040244749 = Nutation in ecliptical longitude +3.461" = +0.0009614909 = Nutation in ecliptical obliquity -0.886s = -0.0036924350 = Equation of the equinoxes Mean Obliquity of the Ecliptic 23° 26' 11.351" = 23.4364863628 True Obliquity of the Ecliptic 23° 26' 14.812" = 23.4374478537
Jay Tanner - PHP Science Labs - 2021 - 1.0