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E Centauri

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E Centauri
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Centaurus
Right ascension 12h 08m 14.70518s[1]
Declination −48° 41′ 33.0323″[1]
Apparent magnitude (V) +5.34[2]
Characteristics
Spectral type B9.5/A0V[3]
B−V color index −0.010±0.007[2]
Astrometry
Radial velocity (Rv)+7.2±0.5[2] km/s
Proper motion (μ) RA: −27.271[1] mas/yr
Dec.: −7.342[1] mas/yr
Parallax (π)5.8040 ± 0.2042 mas[1]
Distance560 ± 20 ly
(172 ± 6 pc)
Absolute magnitude (MV)−0.97[2]
Details
Mass3.38±0.09[4] M
Radius5.835[5] R
Luminosity302+39
−35
[4] L
Surface gravity (log g)3.16[5] cgs
Temperature9,886±69[4] K
Rotational velocity (v sin i)74[4] km/s
Other designations
E Cen, CD−47°7396, FK5 446, GC 16581, HD 105416, HIP 59184, HR 4620, SAO 223235[6]
Database references
SIMBADdata

E Centauri is a single[7] star in the southern constellation of Centaurus. It is a white-hued star that is dimly visible to the naked eye with an apparent visual magnitude of +5.34.[2] The distance to this object is approximately 560 light years based on parallax, and it has an absolute magnitude of −0.97.[2] It is drifting closer to the Sun with a radial velocity of +7 km/s,[2] and it is a candidate member of the Lower Centaurus Crux subgroup of the Sco OB2 association.[8]

This is a late B- or early A-type main-sequence star with a stellar classification of B9.5/A0V,[3] which indicates it is generating energy via core hydrogen fusion. It has 3.4[4] times the mass of the Sun and is spinning with a projected rotational velocity of 74 km/s.[4] The star is radiating 302[4] times the luminosity of the Sun from its photosphere at an effective temperature of 9,886 K.[4]

References

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  1. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d e f g 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. ^ a b Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 2, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H.
  4. ^ a b c d e f g h Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics, 537: A120, arXiv:1201.2052, Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691, S2CID 55586789.
  5. ^ a b McDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017), "Fundamental parameters and infrared excesses of Tycho-Gaia stars", Monthly Notices of the Royal Astronomical Society, 471 (1): 770, arXiv:1706.02208, Bibcode:2017MNRAS.471..770M, doi:10.1093/mnras/stx1433.
  6. ^ "E Cen". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-03-03.
  7. ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  8. ^ Hoogerwerf, Ronnie (March 2000), "OB association members in the ACT and TRC catalogues", Monthly Notices of the Royal Astronomical Society, 313 (1): 43–65, Bibcode:2000MNRAS.313...43H, doi:10.1046/j.1365-8711.2000.03192.x.