Alpha Centauri B
Star
Facts
- Distance
- 4.34 light-years
- Spectral class
- K1 V
- Diameter
- 0.86 times the Sun
- Mass
- 0.91 times the Sun
- IAU name
- Toliman
Alpha Centauri B is the companion of Alpha Centauri A: an orange dwarf of spectral class K1 V, a little smaller and cooler than the Sun. It has 91% of the Sun's mass and shines about half as brightly, and together with Alpha Centauri A it circles their common centre in about 80 years.
The orbit is very elongated, with an eccentricity of 0.52: the distance between the two stars changes a great deal over the 80 years.
Sources
- Akeson et al. 2021, AJ 162, 14 (orbit of Alpha Centauri A and B, table 8)
- Hoffleit and Warren 1991, Yale Bright Star Catalogue, 5th Revised Ed. (V magnitudes, positions and spectral classes)
- IAU WGSN, IAU Catalog of Star Names
- Kervella, Thévenin and Lovis 2017, A&A 598, L7 (Proxima's orbit around Alpha Centauri)