What is the constellation Cepheus?
Cepheus (Cepheus) is a constellation in the northern hemisphere related to the myth of Perseus and Andromeda. It is one of the 88 modern constellations, and also one of the 48 Ptolemaic constellations.
Cepheus: Main Stars
γ Cephei, also known as Alrai, is a binary star approximately 50 light years from Earth. The system has a red dwarf. Due to the precession of the equinoxes, Alrai will be the polar star between the years 3000 and 5000, with a close approach to the north celestial pole around the year 4000.
δ Cephei is the prototype of the Cepheid variable. John Goodricke discovered that this star was variable in 1784. It varies between apparent magnitude 3.5 and 4.3 over a period of 5.4 days.
In this constellation there are three red supergiants that are visible to the naked eye. μ Cephei was named the garnet star by John Herschel, due to its deep red color. It is a semiregular variable star that varies between magnitude 3.4 and 5.1 over a period of 730 days. This star has about 11.8 astronomical units of radius. If it were at the center of our solar system, it would reach the orbit of Saturn. Like μ Cepa, VV Cephei is also variable, between magnitudes 4.8 and 5.4 with a period of about 20 years. The third supergiant is HR 8164, with an apparent magnitude of 5.66.
Kruger 60 is a 10th magnitude binary star consisting of two red dwarfs. Its components are called Kruger 60 A and Kruger 60 B. This star system is only 13 light-years from Earth.
Notable deep sky objects from Cepheus
NGC 188 It is an open cluster that is the closest to the north celestial pole, and one of the oldest. NGC 6946 is a spiral galaxy in which September supernovae have been observed, more than in any other galaxy.
HD 1 is a KO star 1289.2 light years away in the constellation Cepheus.
IC 469 is a spiral galaxy in the constellation Cepheus. It is characterized by a compact core, an oval shape, with noticeable lateral arms.