Astronomy:HR 6875

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Short description: Star in the constellation Corona Australis
HR 6875
Observation data
Equinox J2000.0]] (ICRS)
Constellation Corona Australis
Right ascension  18h 24m 18.24148s[1]
Declination −44° 06′ 36.9008″[1]
Apparent magnitude (V) 5.24[2]
Characteristics
Spectral type B3 V[3]
B−V color index −0.163±0.004[2]
Astrometry
Radial velocity (Rv)+0.00±7.40[2] km/s
Proper motion (μ) RA: −2.949[1] mas/yr
Dec.: −23.107[1] mas/yr
Parallax (π)5.9327 ± 0.2341[1] mas
Distance550 ± 20 ly
(169 ± 7 pc)
Absolute magnitude (MV)−0.63[2]
Details
Mass6.2±0.1[4] M
Radius3.9[5] R
Luminosity (bolometric)1,098[6] L
Temperature20,350[6] K
Rotational velocity (v sin i)248±12[7] km/s
Age103[8] Myr
Other designations
CD−44° 12569, FK5 3461, HD 168905, HIP 90200, HR 6875, SAO 228982, WDS J18243-4407A[9]
Database references
SIMBADdata

HR 6875, previously known as Sigma Telescopii, is a single[10] star in the constellation Corona Australis. It has a blue-white hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.24.[2] This object is located at a distance of approximately 550 light years from the Sun based on parallax.[1] It is listed as a member of the Sco OB2 association.[7]

This is a hot B-type main-sequence star with a stellar classification of B3 V.[3] It is around 103[8] million years old and is spinning rapidly with a projected rotational velocity of 248 km/s or perhaps higher.[7] The star has six[4] times the mass of the Sun and about four[5] times the Sun's radius. It is radiating more than a thousand[6] times the luminosity of the Sun from its photosphere at an effective temperature of 20,350 K.[6]

A magnitude 10.13 visual companion is located at an angular separation of 74 along a position angle of 162°.[11]

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 2.4 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 Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (January 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, doi:10.1111/j.1365-2966.2010.17434.x, Bibcode2011MNRAS.410..190T. 
  5. 5.0 5.1 Pasinetti Fracassini, L. E. et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics 367 (2): 521–524, doi:10.1051/0004-6361:20000451, Bibcode2001A&A...367..521P. 
  6. 6.0 6.1 6.2 6.3 Hohle, M. M. et al. (April 2010), "Masses and luminosities of O- and B-type stars and red supergiants", Astronomische Nachrichten 331 (4): 349, doi:10.1002/asna.200911355, Bibcode2010AN....331..349H. 
  7. 7.0 7.1 7.2 Brown, A. G. A.; Verschueren, W. (1997), "High S/N Echelle spectroscopy in young stellar groups. II. Rotational velocities of early-type stars in SCO OB2", Astronomy and Astrophysics 319: 811, Bibcode1997A&A...319..811B. 
  8. 8.0 8.1 Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters 38 (11): 694–706, doi:10.1134/S1063773712110035, Bibcode2012AstL...38..694G. 
  9. "HD 168905". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+168905. 
  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. Mason, B. D. et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal 122 (6): 3466, doi:10.1086/323920, Bibcode2001AJ....122.3466M, http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=B/wds, retrieved 2015-07-22