Position of the Moon

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the Sun for a day      the Sun for a year

Position of the Sun by Spreadsheet
for a month


download

Select the table 'input': 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.

input
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, May13:00 UT at 50N, 10E:

position sun
        elevation altitude azimuth spreadsheet download Excel

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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).

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


position Sun elevation
        altitude azimuth spreadsheet Excel download


position Sun elevation
        altitude azimuth spreadsheet Excel download

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



1991 May, 00:00 UT mean abs. error
reference
azimuth az
(0.036 0.018) MICA
right ascension RA
(0.0051 0.0012) HORIZONS Web-Interface
declination delta
(0.0025 0.0005) HORIZONS Web-Interface
ecliptic longitude L
(0.0044 0.0016) HORIZONS Web-Interface


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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:

equation of time


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

winter solstice on Dec 22:
solstice

*

sun earth distance

perihelion is on Jan 3:
perihelion

aphelion on Jul 7:
aphelion

***




sun
                      orbit

ecliptic
                      longitude

earth orbit


Download my speadsheet:

sun_month.xlsx (Excel, Windows, Mac)

sun_month.ods (LibreOffice, recommended, Windows, Mac)



sun_month.xlsx



Web Links

Die Zeitgleichung: Eine einfache Formel zu Sonnenaufgang und Untergang

General Solar Position Calculations (PDF)

Solar Calculation Details

MICA (Multiliyear Interactive Computer Almanac), US Naval Observatory

HORIZONS Web-Interface (NASA, JPL)


2019, Aug 10