celestial pole definition of celestial pole in the Free Online Encyclopedia.

celestial pole, one of the two points at which the earth's axis of rotation intersects the celestial sphere celestial 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.
..... Click the link for more information. . The celestial pole is important as a reference point in the equatorial coordinate system equatorial 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 Polaris Polaris (pōlâr`ĭs) or North Star,
..... 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 Crux Crux (kr

ks) [Lat.
..... Click the link for more information. ) points directly to it. The altitude altitude, 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.