Position of the Moon

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Position of the Sun by Spreadsheet
for a day

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 Select the table 'input': Input (red frames): 1) date, month, year 2) geogr. latitude und longitude (eastern longitude positive) Don't modify any other cells. 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.

Example: 1991, May 19 at 50°N, 10°E:

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 (0,0034 ± 0,0022)°.

The refraction is calculated ("elev refr.") by
1.02/(60*tan(K*(elev+10.3/(elev+5.11))))

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The hours of sunrise and sunset are computed by interpolation
(upper limb, airless elevation -50'):

The times agree with MICA and USNO within 1 minute.

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

Comparing the azimuth results "az" of my spreadsheet with the 4 decimal values  of HORIZONS Web-Interface
(NASA JPL) the mean absolute error is (0,0077 ± 0,0024)°.

Diurnal motion of the Sun on May 19 at 50°N, 10°E:

Diurnal motion of the Sun at 50°N, 10°E:

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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 19:

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On 1991, Dec 22, the UT hour of winter solstice is computed:

USNO: 8:54

and on Jun 21, the UT hour of summer solstice:

USNO: 21:19

*

Perihelion on 1991, Jan 3 (0,983281 AU):

USNO: 02:59

Aphelion on Jul 6:

USNO: 15:26

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Position of the Sun in the ecliptic plane (1991, May 19):

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Download my speadsheet:

 sun_day.xlsx   (Excel, Windows, Mac) sun_day.ods   (LibreOffice, recommended, Windows, Mac)

 Web Links MICA (Multiliyear Interactive Computer Almanac), US Naval Observatory USNO Astronomical Applications Department, Sun or Moon Rise/Set Table for One Year

2020, Jan 23