Rho Centauri

Rho Centauri
Location of ρ Centauri (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Centaurus
Right ascension 12h 11m 39.12805s[1]
Declination −52° 22′ 06.4067″[1]
Apparent magnitude (V) +3.97[2]
Characteristics
Evolutionary stage main sequence
Spectral type B3 V[3]
U−B color index −0.650[4]
B−V color index −0.156±0.008[2]
Astrometry
Radial velocity (Rv)+15.0±4.1[5] km/s
Proper motion (μ) RA: −43.741[1] mas/yr
Dec.: −11.771[1] mas/yr
Parallax (π)11.8348 ± 0.3746 mas[1]
Distance276 ± 9 ly
(84 ± 3 pc)
Absolute magnitude (MV)−1.33[2]
Details
Mass6.6±0.1[6] M☉
Radius3.8[7] R☉
Luminosity810.42[2] L☉
Surface gravity (log g)3.95[8] cgs
Temperature19,500[8] K
Rotational velocity (v sin i)147[9] km/s
Age23.7±1.4[6] Myr
Other designations
Rho Cen, ρ Cen, CD−51°6455, HD 105937, HIP 59449, HR 4638, SAO 239737[10]
Database references
SIMBADdata

Rho Centauri, Latinized from ρ Centauri, is a binary star[11] system in the southern constellation of Centaurus. It is visible to the naked eye as a blue-white hued point of light with a combined apparent visual magnitude of +3.97.[2] The system is located approximately 276 light years from the Sun based on parallax, and is drifting further away with a radial velocity of around +15 km/s.[5] It is a proper motion member of the Lower Centaurus–Crux sub-group in the Scorpius–Centaurus OB association, the nearest such association of co-moving massive stars to the Sun.[3]

The primary component of this system is a B-type main-sequence star with a stellar classification of B3 V.[3] It is about 24[6] million years old with a high rate of spin, showing a projected rotational velocity of 147 km/s.[9] It has 6.6[6] times the mass of the Sun and 3.8[7] times the Sun's radius. The star is radiating 810[2] times the luminosity of the Sun from its photosphere at an effective temperature of 19,500 K.[8]

The secondary companion is 1.1 magnitudes fainter than the primary, with a projected separation of 5.68 AU along a position angle of 19.72°, as of 2013.[11]

  1. ^ a b c d e Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d e f Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference aaa216_1_44 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference apjs15 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  6. ^ a b c d Cite error: The named reference mnras410_1_190 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference aaa367_521 was invoked but never defined (see the help page).
  8. ^ a b c Cite error: The named reference levenhagen2006 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference uesugi_fukuda70 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference Rizzuto2013 was invoked but never defined (see the help page).