HD 129116

This article is about b Centauri. For B Centauri, see HD 102964. For β Centauri, see Beta Centauri. Not to be confused with Alpha Centauri B.
b Centauri

b Centauri imaged by VLT/SPHERE. The planet b Centauri b is indicated by an arrow.
Credit: ESO/Janson et al.
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Centaurus
Right ascension 14h 41m 57.59068s[1]
Declination −37° 47′ 36.5940″[1]
Apparent magnitude (V) +4.01[2]
Characteristics
Evolutionary stage Main sequence
Spectral type B3V[3]
B−V color index −0.157±0.002[2]
Variable type Constant[4]
Astrometry
Radial velocity (Rv)+2.6±1.5[2] km/s
Proper motion (μ) RA: −29.828±0.369[5] mas/yr
Dec.: −31.914±0.518[5] mas/yr
Parallax (π)10.0339 ± 0.3143 mas[5]
Distance330 ± 10 ly
(100 ± 3 pc)
Absolute magnitude (MV)−1.07[2]
Details
Mass5–6[6] M☉
Radius2.93±0.12[7] R☉
Luminosity637.01[2] L☉
Surface gravity (log g)4.23±0.03[7] cgs
Temperature18,310±320[6] K
Rotational velocity (v sin i)129[8] km/s
Age15±2[6] Myr
Other designations
b Cen, CD−37°9618, FK5 2985, GC 19779, HD 129116, HIP 71865, HR 5471, SAO 205839[9]
Database references
SIMBADdata

HD 129116 is a binary star in the northeastern part of Centaurus, east of Menkent. It is also known by its Bayer designation of b Centauri, while HD 129116 is the star's identifier in the Henry Draper catalogue. This object has a blue-white hue and is faintly visible to the naked eye with an apparent visual magnitude of +4.01.[2] It is located at a distance of approximately 325 light years (100 parsecs)[5] from the Sun based on parallax, and has an absolute magnitude of −1.07.[2]

The primary star is a hot type-B star with a spectral type of B3V and a mass of 5 to 6 times the solar mass. The secondary star is a close companion separated by approximately 1 AU, with up to 4.4 times the solar mass. In 2021, a massive exoplanet was discovered by direct imaging orbiting the pair of stars (a circumbinary planet) at a distance of about 560 AU.[6]

  1. ^ a b Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d e f g Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Hiltner1969 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Paunzen2017 was invoked but never defined (see the help page).
  5. ^ a b c d Cite error: The named reference EDR3 was invoked but never defined (see the help page).
  6. ^ a b c d Cite error: The named reference Janson2021 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Fitzpatrick2005 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Wolff2007 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).