Sidereal Time Calculator For Any Date, Time and Longitude
PHP Program by Jay Tanner
Local Date
±
Y M D (Neg=BC)
Local Time
HH MM SS (00 to 24h)
Local Time Zone Offset
HH MM (Neg/Pos = W/E)
ΔT (Delta T)
±
HMS
UT
2460670.5
0.268715277778
-0.208333333333
+0.000000000000
Calendar Mode:
Julian
Gregorian
Longitude:
±Deg.ddd or ±D M S (Neg=W)
-76.8233097222
IMPORTANT:
Make sure that the local time, time zone and longitude are correctly matched for the location.
OPTIONAL:
NASA Polynomial ΔT estimate = +74 sec = +00h 01m 14s
Double-Click Within Text Area to Select ALL Text
SIDEREAL TIME FOR GIVEN DATE, TIME AND LONGITUDE Local Date = 2024 Dec 26 [Thursday] Gregorian JD Number = 2460671 JD00 = 2460670.5 = JD for 00h of date Local Time = 06:26:57 = 0.268715277778 day T Zone Diff = -05:00 = -0.208333333333 day Delta T = +00:00:00 = +0.000000000000 day Astronomical Julian Date: JDTT = JDNum - 0.5 + LTFrac - (TZFrac) + (dTFrac) = 2460670.977048611111 Longitude = -76° 49' 23.915" = -76.8233097222° (W) = -05h 07m 17.594s = -5.1215539815 h ================================================================= Local Mean Sidereal Time at Longitude -76.8233097222° (W) 12h 41m 28.818s = 12.6913383808 h 190° 22' 12.27" = 190.3700757120° Local True Sidereal Time at Longitude = -76.8233097222° (W) 12h 41m 28.784s = 12.6913287964 h 190° 22' 11.76" = 190.3699319466° Greenwich Mean Sidereal Time 17h 48m 46.413s = 17.8128923623 h 267° 11' 36.188" = 267.1933854343° Greenwich True Sidereal Time 17h 48m 46.378s = 17.8128827779 h 267° 11' 35.670" = 267.1932416690° ================================================================= Applied Auxiliary Computations Time Factors Corresponding to Full Astronomical JD T = 0.249855634458 Julian centuries reckoned from J2000.0 t = 0.024985563445 Julian millennia reckoned from J2000.0 Circular Trig Functions of Given Longitude Longitude = -76.8233097222° (W) sin(Lon) = -0.973671722605411 cos(Lon) = +0.227954768756023 tan(Lon) = -4.271337370649689 Nutations (IAU 2000B Series) -0.564" = -0.0001566945° = Nutation in ecliptical longitude +8.554" = +0.0023761687° = Nutation in ecliptical obliquity -0.035s = -0.0001437653° = Equation of the equinoxes Mean Ecliptic Obliquity 23° 26' 09.752" = 23.4360423484° Nutation in Obliquity +8.554" = +0.0023761687° True Ecliptic Obliquity 23° 26' 18.307" = 23.4384185171°
Jay Tanner - PHP Science Labs - 2024 - 1.7