Little seems to be known about Kepheus (Cepheus in Latin). He was the King of the Ethiopians, husband of Kasseopeia, and father of Andromeda. He appears in one of the myths involving Perseus.
The constellation is faint and contains little of interest except for three variable stars. The most notable is δ, which is the prototype of a kind of variable star known as a Cepheid variable
. These have regular variations of a distinctive type and their period is related to their intrinsic brightness. Therefore they act as standard candles and their distances can be inferred. Since they are always bright stars they can be seen at great distances and are the primary yardstick for distances out to the nearer galaxies. μ is so red that Herschel called it the Garnet Star
and it varies in an irregular way between magnitudes 3.4 and 5.1. Finally VV Cephei, close to ξ, is a huge eclipsing variable with a small range of 4.7 to 5.4. It appears to be a huge red giant orbited by a small, hot, blue companion in a period of 20.3 years. (The last eclipse occurred in 1996.) The supergiant is believed to be 1800 times the size of the Sun, in which case it is one of the largest stars known. Although technically in the next-door constellation of Cassiopeia, the open cluster M52 is nearby.
The picture was taken at 00:49 on 20th June 2010 using a Cannon 1000D camera with an 18-mm lens, an exposure of 20 seconds at f/3.5 ISO 1600, and enhanced by increasing the contrast and gamma and reducing the background by balancing the colours. The picture was finally rendered in monochrome.