Alpha Cephei

18 L ☉

Alderamin ( الذراع اليمين / Ad - Dira ʿ u ʾ l - Yamin /, the right arm ') is the proper name of the star α Cephei ( Alpha Cephei ).

Alderamin has an apparent magnitude of 2.45 mag and belongs to the spectral class A7. The luminosity class of the star is IV, that is, It is in this star around a subgiant, which transforms from a main-sequence star in a giant star. Its surface is about 7600 Kelvin hot. He has about 18 times the luminosity of our Sun, the mass 1.9 times and about 2.5 times the diameter. The distance from Alderamin is 49 light-years.