Pole Star, or Polaris, is the nearest star to the celestial pole (q.v.), being, in fact, only about 1-1/2° away. This distance, however, is not constant, owing to the fact that the earth's axis does not remain absolutely fixed in direction. [Precession.] On account of its small distance from the pole, it will be seen during the night to move in a very small circle about that imaginary point, a star farther from the pole describing a correspondingly larger circle. Polaris is often used in determinating the exact position of the celestial pole, which may be found by halving the distance between its upper and lower culminations (q.v.). It is quite easy to find Polaris in the sky, for a line joining the two "pointers" of the Great Bear passes very nearly through it.