int = PlanetInConstellationID(nDate, nTimeOfDay, nPlanetID, nMoonSourceIndex, bTopocentric)

 

This macro function returns the ID of the astronomical constellation in which the planet nPlanetID is, at nTimeOfDay on nDate, using the Moon data source of index nMoonSourceIndex.

 

•The allowed values for nPlanetID range from n_MERCURY to n_PLUTO, and also include n_SUN and n_MOON.

•The ID being returned by this function is an internal ID, which follows the order in which they are listed on the International Astronomical Union (IAU) website, but only the names and abbreviations are official.

•If bTopocentric is true, the position is as seen from the location of the selected Moon data source. If it is false, the position is as seen from the centre of the Earth.

•The value of the parameter nTimeOfDay must be supplied to the function in one millionth of a day (less than 1/10th of a second), preferably using the function MillionFromHMS to avoid any error.

 

The function identifies the IAU constellation region containing the body's position. This is distinct from an astrological zodiac sign, which is defined by a division of ecliptic longitude.

 

See also: PlanetInConstellationAbbreviation and PlanetInConstellationName.

 

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Topic 179950, last updated on 11-Oct-2026