Astronomy:Upsilon Coronae Borealis

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Short description: Star in the constellation Corona Borealis
Upsilon Coronae Borealis
Corona Borealis charta.png
Red circle.svg
Location of υ CrB (red circle)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Corona Borealis
Right ascension  16h 16m 44.78733s[1]
Declination +29° 09′ 00.9399″[1]
Apparent magnitude (V) 5.78[2]
Characteristics
Spectral type A3V[3]
U−B color index +0.10[2]
B−V color index +0.07[2]
Astrometry
Radial velocity (Rv)0.8±1.0[4] km/s
Proper motion (μ) RA: +23.474[1] mas/yr
Dec.: −16.644[1] mas/yr
Parallax (π)5.1783 ± 0.0777[1] mas
Distance630 ± 9 ly
(193 ± 3 pc)
Absolute magnitude (MV)−0.72[5]
Details
Mass3.06±0.19[6] M
Radius1.5[7] R
Luminosity151[8] L
Temperature8,098[8] K
Rotational velocity (v sin i)112[3] km/s
Other designations
υ CrB, 18 Coronae Borealis, NSV 7596, BD+29°2803, FK5 3287, HD 146738, HIP 79757, HR 6074, SAO 84281, WDS J16167+2909[9]
Database references
SIMBADdata

Upsilon Coronae Borealis, Latinized from υ Coronae Borealis, is a solitary[10] star in the northern constellation of Corona Borealis. It is a white-hued star that is dimly visible to the naked eye with an apparent visual magnitude of 5.78.[2] The distance to this object is approximately 630 light-years (190 parsecs) based on parallax.[1]

This is an A-type main-sequence star with a stellar classification of A3V;[3] a star that is currently fusing its core hydrogen. However, Palmer et al. (1968) had it classed as type A2IV,[11] and thus it may be near or past its main sequence lifetime.[6] It is a suspected variable star of unknown type that has been measured ranging in brightness from magnitude 5.78 down to 5.88.[12]

Upsilon Coronae Borealis has three[6] times the mass of the Sun and about 1.5[7] times the Sun's radius. It is spinning with a projected rotational velocity of 112 km/s.[3] The star is radiating 151[8] times the luminosity of the Sun from its photosphere at an effective temperature of 8,098 K.[8]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 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 Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99): 99, Bibcode1966CoLPL...4...99J. 
  3. 3.0 3.1 3.2 3.3 Royer, F. et al. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics 463 (2): 671–682, doi:10.1051/0004-6361:20065224, Bibcode2007A&A...463..671R. 
  4. de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics 546: 14, doi:10.1051/0004-6361/201219219, A61, Bibcode2012A&A...546A..61D. 
  5. Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  6. 6.0 6.1 6.2 Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy and Astrophysics 537: A120, doi:10.1051/0004-6361/201117691, Bibcode2012A&A...537A.120Z. 
  7. 7.0 7.1 Pasinetti Fracassini, L. E.; Pastori, L.; Covino, S.; Pozzi, A. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics 367: 521–524, doi:10.1051/0004-6361:20000451, Bibcode2001A&A...367..521P. 
  8. 8.0 8.1 8.2 8.3 McDonald, I. et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society 427 (1): 343–57, doi:10.1111/j.1365-2966.2012.21873.x, Bibcode2012MNRAS.427..343M. 
  9. "ups CrB". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=ups+CrB. 
  10. 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. 
  11. Palmer, D. R. et al. (1968), "The radial velocities spectral types and projected rotational velocities of 633 bright northern A stars", Royal Observatory Bulletin 135: 385, Bibcode1968RGOB..135..385P. 
  12. Samus', N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (2017), "General catalogue of variable stars: Version GCVS 5.1", Astronomy Reports 61 (1): 80, doi:10.1134/S1063772917010085, Bibcode2017ARep...61...80S.