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Center::latitude    Style::horizon    Equator::stars    Almanac::circle    System::north    Title::negative

{{#invoke:Hatnote|hatnote}} In astronomy, declination (abbreviated dec; symbol δ) is one of the two angles that locate a point on the celestial sphere in the equatorial coordinate system, the other being hour angle. Declination's angle is measured north or south of the celestial equator, along the hour circle passing through the point in question.<ref> {{#invoke:citation/CS1|citation |CitationClass=book }} </ref>

Right ascension and declination as seen on the inside of the celestial sphere. The primary direction of the system is the vernal equinox, the ascending node of the ecliptic (red) on the celestial equator (blue). Declination is measured northward or southward from the celestial equator, along the hour circle passing through the point in question.

The root of the word declination (Latin, declinatio) means "a bending away" or "a bending down". It comes from the same root as the words incline ("bend toward") and recline ("bend backward").<ref> {{#invoke:citation/CS1|citation |CitationClass=book }} </ref>


Declination sections
Intro  Explanation   Effects of precession   Stars  Sun  Relation to latitude  See also  Notes and references   External links   

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