Triple star system in the constellation Centaurus
Xi2 Centauri ,Latinized from ξ2 Centauri, is atriple star [ 12] constellation ofCentaurus . It is visible to the naked eye with anapparent visual magnitude of 4.30,[ 2] optical double with the slightly dimmerξ1 Centauri .[ 13] parallax shift of 6.98 mas , Xi2 Centauri lies roughly 470 light years from theSun . At that distance, the visual magnitude is diminished by an interstellarextinction factor of 0.32 due to intervening dust.[ 14]
This system was discovered to be a single-linedspectroscopic binary in 1910 by American astronomerJoseph Haines Moore .[ 15] [ 16] period of 7.6497 days and aneccentricity of 0.35.[ 8] B-type star with astellar classification of B1.5 V[ 4] [ 5] main sequence star or a moreevolved subgiant star . It has about 8.1[ 4] mass of the Sun and radiates 1,702 times thesolar luminosity from itsouter atmosphere at aneffective temperature of 20,790 K.[ 9] hybrid pulsator and shows spacings in both g and p modes.[ 17]
A third star, component B, is a magnitude 9.38F-type main sequence star with a classification of F7 V. It has 1.25[ 9] [ 9] [ 9] angular separation of 25.1 arc seconds from the inner pair.[ 3] common proper motion , indicating they may be gravitationally bound with an orbital period of around 41,000 years.[ 18]
The system has apeculiar velocity of± 4.2 km/s[ 6] Scorpius–Centaurus association and appears to be a member of theGould's Belt .[ 19]
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