Polaris

or North Star

Earth's present northern polestar (the star visible from the Northern Hemisphere toward which Earth's axis points), at the end of the “handle” of the Little Dipper in the constellation Ursa Minor. Polaris is actually a triple star, composed of a binary star and a Cepheid variable. Precession of Earth's axis made the star Thuban, in the constellation Draco, the North Star in ancient Egyptian times; it will cause the North Pole to point toward Vega, in the constellation Lyra, 12,000 years from now.

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