Upsilon1 Centauri, Latinized from υ1 Centauri, is a single[8] star in the southern constellation of Centaurus. It has a blue-white hue and is visible to the naked eye with an apparent visual magnitude of +3.87.[2] The distance to this object is approximately 427 light years based on parallax,[1] and is receding with a radial velocity of +9 km/s.[4] It is a member of the Lower Centaurus Crux group of the Scorpius–Centaurus association.[2]

υ1 Centauri
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Centaurus
Right ascension 13h 58m 40.75s[1]
Declination −44° 48′ 12.9″[1]
Apparent magnitude (V) +3.87[2]
Characteristics
Spectral type B2 IV/V[3]
B−V color index −0.208±0.011[2]
Astrometry
Radial velocity (Rv)+9.2±1.4[4] km/s
Proper motion (μ) RA: −27.51±0.15[1] mas/yr
Dec.: −22.44±0.13[1] mas/yr
Parallax (π)7.63 ± 0.16 mas[1]
Distance427 ± 9 ly
(131 ± 3 pc)
Absolute magnitude (MV)−1.72[2]
Details
Mass7.9±0.1[5] M
Radius3.74±0.34[6] R
Luminosity1,884[2] L
Surface gravity (log g)4.15±0.07[6] cgs
Temperature21,411±377[6] K
Rotational velocity (v sin i)124[4] km/s
Age13.0±2.0[5] Myr
Other designations
υ1 Cen, CD−44° 9010, FK5 3112, HD 121790, HIP 68282, HR 5249, SAO 224585[7]
Database references
SIMBADdata

The stellar classification of this object is B2 IV/V,[2] matching a massive B-type star with a luminosity class displaying mixed traits of a main sequence and a subgiant star. It is 13[5] million years old and is spinning with a projected rotational velocity of 124 km/s.[4] The star has 7.9[5] times the mass of the Sun and 3.7[6] times the Sun's radius. It is radiating 1,884[2] times the luminosity of the Sun from its photosphere at an effective temperature of 21,411 K.[6]

References

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  1. ^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600. Vizier catalog entry
  2. ^ a b c d e f g h Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  3. ^ Hiltner, W. A.; et al. (July 1969), "MK Spectral Types for Bright Southern OB Stars", Astrophysical Journal, 157: 313–326, Bibcode:1969ApJ...157..313H, doi:10.1086/150069.
  4. ^ a b c d Jilinski, E.; et al. (March 2006), "Radial velocity measurements of B stars in the Scorpius–Centaurus association", Astronomy and Astrophysics, 448 (3): 1001–1006, arXiv:astro-ph/0601643, Bibcode:2006A&A...448.1001J, doi:10.1051/0004-6361:20041614, S2CID 17818058.
  5. ^ a b c d Tetzlaff, N.; et al. (2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.
  6. ^ a b c d e Fitzpatrick, E. L.; Massa, D. (March 2005), "Determining the Physical Properties of the B Stars. II. Calibration of Synthetic Photometry", The Astronomical Journal, 129 (3): 1642–1662, arXiv:astro-ph/0412542, Bibcode:2005AJ....129.1642F, doi:10.1086/427855, S2CID 119512018.
  7. ^ "ups01 Oph". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-21.
  8. ^ Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.