It is listed as a possible eclipsing binary with a very small amplitude. (2008) have detected a periodicity of 533 days, hinting at the possible presence of an as yet unseen companion. The star has a metallicity approximately 1.6 times that of the Sun i.e., it contains 1.6 times as much heavy-element material as the Sun. At a distance of about 840 light-years, Zeta Cephei has an apparent magnitude ( m) of 3.4 and an absolute magnitude ( M) of -4.7. The luminosity of Zeta Cephei is approximately 3,600 times that of the Sun. Zeta Cephei is an orange supergiant star with a surface temperature of 3,853 K and eight times more massive than the Sun. It is one of the fundamental stars of the MK spectral sequence, defined as type K1.5 Ib. Zeta Cephei marks the left shoulder of Cepheus, the King of Joppa ( Ethiopia). Zeta Cephei (ζ Cep, ζ Cephei) is a star in the constellation of Cepheus.
