Tags: Star.
X Persei is a binary star system located in the constellation Perseus.X Persei A is either an O-type giant or a B-type main sequence star which is orbited by a Neutron Star (X Persei B). With an apparent magnitude of 6.72 it is too dim to seen even on the best nights. The system is an X-ray source and the primary star appears to be suffering from substantial mass loss.