Tau_Centauri
Tau Centauri
White-hued star in the constellation Centaurus
Tau Centauri, Latinized from τ Centauri, is a solitary[11] star in the southern constellation of Centaurus. It is visible to the naked eye with an apparent visual magnitude of +3.86.[2] The distance to this star, based upon an annual parallax shift of 24.85 mas,[1] is 131 light years. There is a 98% chance that it is a co-moving companion of Gamma Centauri; the two stars have an estimated separation of 1.7 ly (0.53 pc).[12]
This is an A-type star with stellar classifications of A0 V[3] or A1 IVnn,[4] indicating it may be a main sequence star or a more evolved subgiant star. It is around 132[7] million years old and is spinning rapidly with a projected rotational velocity of 296.8[9] km/s. This is giving the star an oblate shape, with an estimated equatorial girth that is 30% larger than the polar radius.[13] The star has an estimated 2.3[7] times the mass of the Sun and 2.2[8] times the Sun's radius.