Word origin · etymology
Latin through French.
Latin declinatio meant a turning aside or an angle of the heavens; the coordinate measures departure from the celestial equator.
How we know · epistemology
Astronomical geometry
Declination is derived from the equatorial frame and can be checked against positional observations. Equal declination does not establish closeness in the sky without also comparing right ascension.
Connected concepts
Mentioned in 3 other entries
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Sources & provenance
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