By clicking on the map the geographic latitude and longitude is used for the calculations.

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)

Date UTC Latitude (N pos.) Longitude (E pos.) Julian Date
° ° 2460475.8966
Solar Position R. A. 83.27° Decl. 23.29° Dist. (AU) 1.016 App. Diam. 1890.33"
Phys. Ephem. P -9.856° Bo 0.971° Lo 205.297° Carr # 2285
Pos. @ KSO Azim. 133.09° Height 59.98° Noon 11:04:47 Heightnoon 66.62°
Horizon (H=0°):  Sunrise 03:10:09 Sunset 18:59:36 Daylength 15:49:27
Orographic Horizon:  Sunrise 03:38:13 Sunset 18:50:58 Daylength 15:12:45

There exists also an API to get these values:
returns all values for the location of the Observatory at 13:26:56 on June 7 2022
returns only the Julian Date for the location of the Observatory at 13:26:56 on June 7 2022
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 Aszension[deg] Decl Declination[deg]
Dist Distanz[AU] Dia Diameterer{arcsec] H Height[deg] Az Azimuth[deg]
Rise Sunrise[UTC] Set Sunset[UTC] Noon Noon[UTC] NoonH Height at Noon
P Polar Angle[deg] B0 Inclination[deg] Lon Heliogr. Longitude[deg]Carr Carrington Rotation
Input Values

Day for calculation in the format yyyymmdd.
Time in UTC in the format hh:mm:ss. The calculations are done in UTC - no correction for time zones!
Latitude of the observer in degrees, North is positive.
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.
Declination of the Sun.
Distance of the Sun, measured in astronomical units (A. U.)
App. Diam.
Apparent diameter of the Solar disk, measured in arc seconds.
Position angle of the northern extremity of the axis of Solar rotation, measured eastwards from the North point of the Solar disk.
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).
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
Azimuth of the Sun at observers position, measured from North eastwards.
Height of the Sun above Horizon at observers position. Not corrected for refraction!
Sunrise, Sunset
Sunrise and Sunset at observers position in Universal Time Coordinated (UTC). 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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Uni Graz   Editor