Astronomy:HR 6594

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Short description: Binary star system in the constellation of Hercules
HR 6594
Observation data
Equinox J2000.0]] (ICRS)
Constellation Hercules
Right ascension  17h 41m 58.632s[1]
Declination +15° 57′ 08.76″[1]
Apparent magnitude (V) 5.54[2]
Characteristics
Evolutionary stage Main sequence[3]
Spectral type F4 Vw[4]
U−B color index −0.05[5]
B−V color index +0.387±0.012[2]
Astrometry
Radial velocity (Rv)−43.7[6] km/s
Proper motion (μ) RA: −1.868[1] mas/yr
Dec.: +101.120[1] mas/yr
Parallax (π)28.5131 ± 0.0532[1] mas
Distance114.4 ± 0.2 ly
(35.07 ± 0.07 pc)
Absolute magnitude (MV)2.74[7]
Details
HR 6594 A
Mass1.34[8] M
Radius0.97[9] R
Luminosity6.17[2] L
Surface gravity (log g)4.07[3] cgs
Temperature6,615[3] K
Metallicity [Fe/H]−0.04[10] dex
Rotational velocity (v sin i)31.7[3] km/s
Age1.2[8] Gyr
Other designations
BD−16° 3256, HD 160910, HIP 86623, HR 6594, SAO 103033[11]
Database references
SIMBADdata

HR 6594 is the Bright Star Catalogue designation for a binary star[12] system in the northern constellation of Hercules. It is faintly visible to the naked eye with an apparent visual magnitude of 5.54;[2] according to the Bortle scale, it is sufficiently bright to be visible from dark suburban skies. The distance to this system, as determined using parallax measurements,[1] is about 114 light years. It is drifting closer with a heliocentric radial velocity of −43.7 km/s,[6] and is predicted to come as near as 47 light-years in 686,000 years.[2] On the celestial sphere it is located near the star Alpha Ophiuchi; their projected separation is just 3 light years, although their actual separation is much greater.[13]

The primary is an F-type main sequence star with a stellar classification of F4 Vw, where the w indicates relatively weak metallic features in the ultraviolet spectrum.[4] This star has 134% of the Sun's mass,[8] but only 97% of the solar radius.[9] It is spinning with a projected rotational velocity of 31.7 km/s,[3] and is around 1.2 billion years old.[8] The effective temperature of the outer atmosphere is 6,615 K,[3] giving it the yellow-white hue of an F-type star.[14] The abundance of elements other than hydrogen or helium, what astronomers term the metallicity, is similar to that in the Sun.[10]

It has a magnitude 9.38 companion star orbiting with a 144-year period, a semimajor axis spanning 1.04 arcseconds, and an eccentricity of 0.42.[12] There is a third, visual companion of magnitude 14.46 at an angular separation of 154.70 arcseconds along a position angle of 271°, as of 2001.[15]

References

  1. Jump up to: 1.0 1.1 1.2 1.3 1.4 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode2021A&A...649A...1G.  Gaia EDR3 record for this source at VizieR.
  2. Jump up to: 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. Jump up to: 3.0 3.1 3.2 3.3 3.4 3.5 Schröder, C. et al. (January 2009), "Ca II HK emission in rapidly rotating stars. Evidence for an onset of the solar-type dynamo", Astronomy and Astrophysics 493 (3): 1099–1107, doi:10.1051/0004-6361:200810377, Bibcode2009A&A...493.1099S, http://goedoc.uni-goettingen.de/goescholar/bitstream/handle/1/9690/aa10377-08.pdf?sequence=2. [yes|permanent dead link|dead link}}]
  4. Jump up to: 4.0 4.1 Barry, Don C. (1970), "Spectral Classification of A and F Stars", Astrophysical Journal Supplement 19: 281, doi:10.1086/190209, Bibcode1970ApJS...19..281B. 
  5. Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data (SIMBAD), Bibcode1986EgUBV........0M. 
  6. Jump up to: 6.0 6.1 Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication (Carnegie Institute of Washington D.C.), Bibcode1953GCRV..C......0W. 
  7. Boesgaard, A. M.; Tripicco, M. J. (April 15, 1986), "Lithium in early F dwarfs", Astrophysical Journal, Part 1 303: 724–739, doi:10.1086/164120, Bibcode1986ApJ...303..724B. 
  8. Jump up to: 8.0 8.1 8.2 8.3 David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal 804 (2): 146, doi:10.1088/0004-637X/804/2/146, Bibcode2015ApJ...804..146D. 
  9. Jump up to: 9.0 9.1 Pasinetti-Fracassini, L. E. et al. (February 2001), "Catalogue of Stellar Diameters (CADARS)", Astronomy and Astrophysics 367: 521–524, doi:10.1051/0004-6361:20000451, Bibcode2001A&A...367..521P. 
  10. Jump up to: 10.0 10.1 Casagrande, L. et al. (2011), "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey", Astronomy & Astrophysics 530 (A138): 21, doi:10.1051/0004-6361/201016276, Bibcode2011A&A...530A.138C. 
  11. "HR 6594". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HR+6594. 
  12. Jump up to: 12.0 12.1 Malkov, O. Yu. et al. (October 2012), "Dynamical masses of a selected sample of orbital binaries", Astronomy & Astrophysics 546: 5, doi:10.1051/0004-6361/201219774, A69, Bibcode2012A&A...546A..69M. 
  13. Redfield, Seth et al. (June 2007), "Spitzer Limits on Dust Emission and Optical Gas Absorption Variability around Nearby Stars with Edge-on Circumstellar Disk Signatures", The Astrophysical Journal 661 (2): 944–971, doi:10.1086/517516, Bibcode2007ApJ...661..944R. 
  14. "The Colour of Stars", Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004, http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html, retrieved 2012-01-16. 
  15. Mason, B. D. et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal 122 (6): 3466–3471, doi:10.1086/323920, Bibcode2001AJ....122.3466M, http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=B/wds, retrieved 2015-07-22.