Position of the Moon by speadsheet

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the Moon for a day the Moon for a year

Position of the Moon by Spreadsheet
for a month

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Select the table 'input':
Input (red frames): 1) hour UT, min 2) 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. Don't edit any cell.
Select 'elev az _illum' to see data and diagrams of elevation, azimut and illumination.
Select 'distance declin' to see data and diagrams of geocentric distance and declination.
Select 'orbit' to see the orbit of the Moon around the Earth.
Select 'L B' to see data and diagrams of ecliptic longitude and latitude.
Select 'sol ecl' to explore solar eclipses.
Select 'lun ecl' to explore lunar eclipses.

Example: 2000, Jan, 0:00 UT at 50°N, 10°E:

position
moon elevation altitude spreadsheet download

Comparing the results of airless elevation of my spreadsheet with the 4 decimal places of MICA
the mean absolute error is only (0,036 ± 0,018)°.

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The illuminated fraction k of the moon is geocentric, computed (Meeus, Astronomical Algorithms, Ch. 46) by:
k = [1+cos(i)]/2
cos(i)= cos(Bmoon) cos(Lmoon-Lsun)

moon year
position Excel spreadsheet download

moon year
position Excel spreadsheet download

Comparing my results for the illuminated fraction of the spreadsheet (geocentric) with the 1 decimal values of MICA
the error is (0,02 ± 0,03) %.

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moon position
spreadsheet excel download

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

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Position of the Moon, on 2000 Jan, 0 UT at 50°N, 10°E:

moon position elevation
altitude azimuth

moon position elevation
altitude azimuth

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Geocentric distance and declination

2000, Jan, 0:00 UT

The geocentric distance of the Moon is computed by Meeus (Astronomical Algorithms, Table 45.A, 46 trigonometric terms):

The mean absolute error in Jan 2000 at 0 UT is (3.0 ± 1.7) km,
reference: MICA

error
distance

The mean absolute error |∆R| on Jan 1 at 00:00 UT in 1850 to 2050 is (3.3 ± 3.0) km,
reference: MICA

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topocentric distance

At 50°N 0°E the mean abs. error in Oct. 2022 at 00:00 UT (reference MICA) is
(3.4 ± 2.6) km

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topocentric
distance of the moon

2022 Jan at 50°N 0°E

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The topocentric diameter of the Moon, 2000 Jan at 00:00 UT:
moon apparent
diameter

The diameter is computed by the equatorial horizontal parallax (Meeus, Astronomical Algorithms, ch. 39, 53).

Comparing the results "diam" of my spreadsheet with the values of HORIZONS Web-Interface
(NASA JPL) the mean absolute errors "∆diam" are in arcmin:

moon
apparent diameter

A large full moon occured on 2019, Feb 19 at 00:00: diameter 33.97 arcmin (HORIZONS Web-Interface) ***

The extremes in the Moon's negative/positive declination ranges
from about -18.2° to -28.7° and +18.2° to +28.7° in a period of 18.6 years:

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The orbit of the Moon around the Earth (Jan 2000):

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Ecliptic longitude Lm and latitude Bm

2000, Jan, 0:00 UT
moon
latitude

Download speadsheet (Windows und Mac):

moon_month.xlsx (MS Excel)

moon_month.ods (LibreOffice, recommended)

Updated!

Web Links

Die Zeitgleichung: Eine einfache Formel zu Sonnenaufgang und Untergang

General Solar Position Calculations (PDF)

Solar Calculation Details

MICA (Multiliyear Interactive Computer Almanac 1800-2051), US Naval Observatory 2011, no longer published

Monthly Lunar Standstills: 2001 to 2100

2022, Oct. 23