Position of the Sun by Spreadsheet
for a month

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Select the table 'input':
Input (red frames): 1) hour UT, min 2) date: month, year 3) geogr. latitude und longitude     (eastern longitude positive) Don't modify any other cell.
The table calc performs the calculations, using a lot of auxiliary variables. It should be neglected.
Select elev az to see data and diagrams of elevation and azimuth.
Select E o T for data and diagrams of the Equation of Time.
Select declin  dist to see data and diagrams of the declination and distance.
Select orbit to see data and a diagram of the ecliptic orbit.

The value "elev" is not taking into account the atmospheric refraction.

Comparing the results "elev" (airless) of the spreadsheet with (4 decimal places) of HORIZONS Web-Interface
(NASA JPL) the mean absolute error is only (0,0058 ± 0,0011)°.

Azimuth is measured North(0°) -> East(90°) -> South(180°) -> West(270°) -> North (360°).

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The equation of time can by computed (neglecting nutation in longitude) by
E = L₀ - 0.0057183° - RA
EoT = 4*E in minutes

Example: 1991, May at 00:00 UT:

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In 1991, March, the summer solstice is computed: Mar 22.


winter solstice on Dec 22:


*

perihelion is on Jan 3:


aphelion on Jul 7:

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Download my speadsheet:

sun_month.xlsx