When is the best time to observe Zeta Cephei?

Zeta Cephei is best observed from July through September, with peak visibility during August when it transits around midnight in the Northern Hemisphere.

Where is Zeta Cephei located in the sky?

Zeta Cephei lies in the constellation Cepheus at right ascension 22h 11m and declination +58° 12′.

What telescope do I need to see Zeta Cephei?

At magnitude 3.4, Zeta Cephei is visible to the naked eye from dark skies, easy in any binoculars.

Zeta Cephei — Star in Cepheus

Magnitude 3.4^m Star Cepheus (Cep) Visible

Star Map + List + Plan

About Zeta Cep

Description

Zeta Cephei is an orange supergiant of spectral type K1.5Ib at magnitude 3.35 in Cepheus. Located about 730 light-years from Earth, it is a luminous evolved star with roughly 3,600 times the Sun's luminosity and a diameter about 110 times solar. It is one of the more distant supergiant stars visible to the naked eye in the northern sky.

Observing Tips

Zeta Cep lies in the southern part of Cepheus, the house-shaped constellation near Cassiopeia and the north celestial pole. It is circumpolar from most northern latitudes. Its warm orange color is apparent in binoculars. Best observed from August through December when Cepheus is high in the evening sky.

History

Zeta Cephei has no widely used traditional name. Cepheus represents the king of Ethiopia in Greek mythology, husband of Cassiopeia and father of Andromeda. The constellation is best known for containing Delta Cephei, the prototype of the Cepheid variable stars used to measure cosmic distances.

Fun Facts

Zeta Cep is one of the reddest and most luminous stars in Cepheus. As a K-type supergiant, it is in a brief evolutionary phase — in cosmic terms, it will exhaust its nuclear fuel relatively soon and likely end its life as a supernova or shed its outer layers to become a white dwarf, depending on its exact mass.