Solar Ephemeris Calculation Utility

For calculation of the Solar Ephemeris enter a date in the given format and press the Calculate button! Note: Values valid from the year -2000 to 6000, with an uncertainty of +/- 0.0003 degrees. Source code: SPA calculator from US Department of Energy, (Reference: Reda, I.; Andreas, A., Solar Position Algorithm for Solar Radiation Applications, Solar Energy. Vol. 76(5), 2004; pp. 577-589)

Day [yyyymmdd]	UT [hh:mm:ss]	Latitude (N pos.)		Longitude (E pos.)		Julian Date
		°		°		2459979.9224
Solar Position	R. A.	317.776389^°	Decl.	-16.243087^°	Dist. (AU)	0.9857231	App. Diam.	1947.81^"
Phys. Ephem.	P	-13.4049116^°	B_o	-6.2250961^°	L_o	271.7609077^°	Carr #	2267
Pos. @ KSO	Azim.	161.4015^°	Height	25.1306^°	Sunrise	06:25:05	Sunset	16:11:54

There exists also an API to get these values:

http://cesar.kso.ac.at/info/ephem_api.php?date=20220607&time=13:26:55&lat=46.6783&lon=13.9067

returns all values for the location of the Observatory at 13:26:56 on June 7 2022

http://cesar.kso.ac.at/info/ephem_api.php?date=20220607&time=13:26:55&lat=46.6783&lon=13.9067&JD

returns only the Julian Date for the location of the Observatory at 13:26:56 on June 7 2022

http://cesar.kso.ac.at/info/ephem_api.php?date=20220607&time=13:26:55&lat=46.6783&lon=13.9067&JD&Decl

returns the Julian Date and the declination for the location of the Observatory at 13:26:56 on June 7 2022

the parameters are:

date	Date[yyyymmdd]	time	Time[HH:MM:SS]	lat	geogr. Latitude[deg]	lon	geogr. Longitude[deg]
JD	Julian Date	RA	Right Ascension[deg]	Decl	Declination[deg]	ET	Equation of Time
Dist	Distance[AU]	Dia	Diameter{arcsec]	H	Height[deg]	Az	Azimuth[deg]
Rise	Sunrise[UT]	Set	Sunset[UT]	Noon	Noon[UT]	NoonH	Height at Noon
P	Polar Angle[deg]	B0	Inclination[deg]	Lon	Heliogr. Longitude[deg]	Carr	Carrington Rotation

if date is ommitted the actual day will be used
if time is ommitted the actual time (UT) will be used
default for lat and lon is the KSO position
calling the API without parameters will return the valus of the actual time for KSO

Input Values
Day: Day for calculation in the format yyyymmdd.
Time: Time in UT in the format hh:mm:ss. The calculations are done in UT - no correction for time zones!
Latitude: Latitude of the observer in degrees, North is positive.
Longitude: Longitude of the observer in degrees, East is positive.
Output Values
Julian Date: Consecutively numbered days since Jan 01, 4713 B.C. (days start at noon 12 UTC!)
R. A.: Right Ascension of the Sun.
Decl.: Declination of the Sun.
Dist.: Distance of the Sun, measured in astronomical units (A. U.)
App. Diam.: Apparent diameter of the Solar disk, measured in arc seconds.
P: Position angle of the northern extremity of the axis of Solar rotation, measured eastwards from the North point of the Solar disk.
B_o: Heliographic latitude of the central point of the Solar disk. Angle of inclination of the Solar equator on the Ecliptic (counted positive if Solar North Pole is visible).
L_o: Heliographic longitude of the central point of the Solar disk, measured towards West (i. e. in direction of Solar rotation) from the hypothetical prime meridian which rotates with a mean synodical (Carrington) period of 27.2753 days.
Carr #: Number of Solar rotations since Nov. 9, 1853
Azim.: Azimuth of the Sun at observers position, measured from North eastwards.
Height: Height of the Sun above Horizon at observers position. Not corrected for refraction!
Sunrise, Sunset: Sunrise and Sunset at observers position in Universal Time (UT). Sunrise and Sunset are defined as times where the upper limb of the Solar disk appears to be at the horizon, correction for refraction (≅0.83 deg) under normal conditions is considered.

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