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Related to celestial pole: celestial equator
celestial pole,one of the two points at which the earth's axis of rotation intersects the celestial spherecelestial sphere,
imaginary sphere of infinite radius with the earth at its center. It is used for describing the positions and motions of stars and other objects. For these purposes, any astronomical object can be thought of as being located at the point where the line of sight
..... Click the link for more information. . The celestial pole is important as a reference point in the equatorial coordinate systemequatorial coordinate system,
the most commonly used astronomical coordinate system for indicating the positions of stars or other celestial objects on the celestial sphere. The celestial sphere is an imaginary sphere with the observer at its center.
..... Click the link for more information. ; the celestial meridian passes through it, as do the hour circles of the stars. The polestar (see PolarisPolaris
or North Star,
star nearest the north celestial pole (see equatorial coordinate system). It is in the constellation Ursa Minor (see Ursa Major and Ursa Minor; Bayer designation Alpha Ursae Minoris) and marks the end of the handle of the Little Dipper.
..... Click the link for more information. ) lies within 0.5° of the north celestial pole. Although there is no bright star near the south celestial pole, the Southern Cross (see CruxCrux
[Lat.,=cross], small but brilliant southern constellation whose four most prominent members form a Latin cross, the famous Southern Cross. The long arm of the cross, terminating in the brightest member, Acrux (Alpha Crucis), points almost directly at the south celestial
..... Click the link for more information. ) points directly to it. The altitudealtitude,
vertical distance of an object above some datum plane, such as mean sea level or a reference point on the earth's surface. It is usually measured by the reduction in atmospheric pressure with height, as shown on a barometer or altimeter.
..... Click the link for more information. of the celestial pole in an observer's hemisphere is equal to the observer's latitude on the earth.
celestial pole[sə′les·chəl ′pōl]
Either of the two points of intersection of the celestial sphere and the extended axis of the earth, labeled N or S to indicate the north celestial pole or the south celestial pole.