Template:POTD/2017-05-12

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Cepheus
Cepheus is a constellation in the northern sky. Named after Cepheus, King of Aethiopia, in Greek mythology, it was listed by the 2nd century astronomer Ptolemy and remains one of the 88 modern constellations. Its brightest star is Alpha Cephei. The constellation also has the hyperluminous quasar S5 0014+81, which hosts the most massive black hole known in the universe.

This illustration was included in Urania's Mirror, a set of celestial cards illustrated by Sidney Hall.Illustration: Sidney Hall; restoration: Adam Cuerden