5 articles for "Declination"

**Declination**[Astro*Index]

Distance along the *hour circle* between the *celestial equator* and a *celestial body* measured in degrees. Distance north of the equator is measured positive, south negative.

See also:

♦ Right Ascension ♦ Celestial Coordinates ♦ Hour Circle ♦ Celestial Equator ♦ Celestial Body ♦ Equatorial

**Declination**[Prima]

Declination is the measurement of angular distance above or below the equator (along an hour circle). It is the second angle of measurement of the equatorial system of celestial coordinates (the first is Right Ascension).

See also:

♦ Right Ascension ♦ Celestial Coordinates ♦ Hour Circle ♦ Celestial Equator ♦ Celestial Body ♦ Equatorial

**Declination**[Munkasey M.]

The arc of measurment in degrees along an hour circle, North or South of the Celestial Equator, to a body in space. Always measured as from 0 to 90 degrees. Example: 16 N 27, or 33 5 44. A declination of zero degrees and no minutes indicates that a body is on the Celestial Equator.

See also:

♦ Right Ascension ♦ Celestial Coordinates ♦ Hour Circle ♦ Celestial Equator ♦ Celestial Body ♦ Equatorial

**Declination**[DeVore]

The manner of indicating distance N. or S. of the Celestial Equator. The maximum possible declination of the Sun is 23° 28' which occurs at the Solstices, when the Sun passes the Tropics (0°) of Cancer and Capricorn, the limit of the pole's greatest inclination from the plane of the Earth's orbit. The first degrees of Aries and Libra have no declination, since at these points the ecliptic intersects the equator. However, planets at this longitude may have declination. (v. Celestial Sphere.)

The declination of a body whose longitude and latitude are known, is found by this formula:

**Radius (10,000):**Tangent of Ecliptic (23° 27'):: sine of longitudinal distance from equinox: tangent of Angle A.**Cosine of Angle A:**cosine (latitude plus/minus 90°- minus Angle A):: cosine of Ecliptic Obliquity (23° 27'): sine of the Declination.

(In this equation the latitude is taken from go, if the latitude and longitude are of different denomination; but when of the same denomination they are added, and from this sum Angle A is subtracted.)

The Moon, Mercury, Mars reach a declination of 27° north, and on rare occasions Venus reaches 28°. Jupiter, Saturn, Uranus and Neptune have practically the same declination as the Sun.

♦ Right Ascension ♦ Celestial Coordinates ♦ Hour Circle ♦ Celestial Equator ♦ Celestial Body ♦ Equatorial

**Declination Circle**[Astro*Index]

In astrology, any small circle parallel to the *celestial equator*. Also a setting circle on the declination axis of an equatorially mounted telescope that allows the telescope to be set at the *declination* of a celestial body.

See also: ♦ Celestial Equator ♦ Declination

Astro*Index Copyright © 1997 Michael Erlewine

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