Rho2 Cephei
Rho2 Cephei, Latinized from ρ2 Cephei, or simply ρ Cephei, is a solitary star in the northern constellation of Cepheus. With an apparent visual magnitude of 5.50, it is faintly visible to the naked eye, forming an optical pair with Rho1 Cephei. Based upon an annual parallax shift of as seen from the Earth, it is located about 240 light years from the Sun.
Rho2 Cephei is an A-type main sequence star with a stellar classification of A3 V, estimated to be 85 million years old. It has a high rate of rotation, showing a projected rotational velocity of 133 km/s. The effective temperature of its photosphere is and its bolometric luminosity, the total amount of radiation it emits at all wavelengths, is.
This star has been called by the Arabic name Al Kalb al Rāʽi, the Shepherd's Dog, which is better known as a name for β Ophiuchi.