Tags: Star.
3 Centauri is a binary star in the constellation Centaurus. It is approximately 340 light years from Earth.The primary component 3 Centauri A is a blue-white B-type giant with a mean apparent magnitude of +4.56. It is a variable star and its brightness varies from magnitude +4.27 to +4.32 It is suspected the variations in luminosity are a result of the primary being an eclipsing binary which would mean the system would consist of at least three objects.