Gamma Centauri, Latinized from γ Centauri, is a binary star system in the southernconstellation of Centaurus. It has the proper name Muhlifain,[10] not to be confused with Muliphein, which is γ Canis Majoris; both names derive from the same Arabic root. The system is visible to the naked eye as a single point of light with a combined apparent visual magnitude of +2.17;[2] individually they are third-magnitude stars.[3]
This system is located at a distance of about 130 light-years (40 parsecs) from the Sun based on parallax. In 2000, the pair had an angular separation of 1.217 arcseconds with a position angle of 351.9°.[3] Their positions have been observed since 1897, which is long enough to estimate an orbital period of 84.5 years and a semimajor axis of 0.93 arcsecond.[11][8] At the distance of this system, this is equivalent to a physical separation of about 93 AU.[12]
The combined stellar classification of the pair is A1IV+;[4] when they are separated out they have individual classes of A1IV and A0IV,[5] suggesting they are A-typesubgiant stars in the process of becoming giants. The star Tau Centauri is relatively close to Gamma Centauri, with an estimated separation of 1.72 light-years (0.53 parsecs).[9] There is a 98% chance that they are co-moving stars.[8]
^ abcdJohnson, H. L.; et al. (1966). "UBVRIJKL photometry of the bright stars". Communications of the Lunar and Planetary Laboratory. 4 (99): 99. Bibcode:1966CoLPL...4...99J.
^ abcFabricius, C.; Makarov, V. V. (April 2000). "Two-colour photometry for 9473 components of close Hipparcos double and multiple stars". Astronomy and Astrophysics. 356: 141–145. Bibcode:2000A&A...356..141F.