Perseus

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Perseus (astronomy), constellation in the northern hemisphere of the celestial sphere. Perseus is near the constellations Cassiopeia, Andromeda, Aries, and Taurus. The constellation represents Perseus, a mortal hero of Greek mythology.

Perseus’s brightest star is the yellow super giant Mirfak. The constellation’s second brightest star, Algol, is the best known of all eclipsing binary stars. It loses and regains more than twice its normal brightness every three days. In 1901 light from an exploding star in the center of the constellation was detected by observers on the earth. The star increased in brightness more than 100,000 times, making it one of the brightest novas of recent centuries. Within three days it faded.

Perseus is visible throughout all of the northern hemisphere and the northern two-thirds of the southern hemisphere. It reaches its highest point in the night sky in December.

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