Astronomy:E Centauri

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Short description: B-type or A-type main sequence star in the constellation Centaurus
E Centauri
Observation data
Equinox J2000.0]] (ICRS)
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[1] mas
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

  1. 1.0 1.1 1.2 1.3 1.4 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  3. 3.0 3.1 Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, 2, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode1978mcts.book.....H. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics 537: A120, doi:10.1051/0004-6361/201117691, Bibcode2012A&A...537A.120Z. 
  5. 5.0 5.1 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, doi:10.1093/mnras/stx1433, Bibcode2017MNRAS.471..770M. 
  6. "E Cen". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=E+Cen. 
  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, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E. 
  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, doi:10.1046/j.1365-8711.2000.03192.x, Bibcode2000MNRAS.313...43H.