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Its story

Theta Cephei is a white A7-type star about 136 light-years away, a spectroscopic binary betrayed by the periodic wobble of its light. It belongs to Cepheus, the mythical king and husband of Cassiopeia, and forms part of the Celestial Hook of Chinese astronomy, a faint line traced through the constellation. Hard to spot from a city, in a dark sky it emerges with quiet poise.