HD 134064

(Redirected from NGC 5856)

HD 134064 is a binary star system in the northern constellation of Boötes. It is faintly visible to the naked eye with a combined apparent visual magnitude of 6.03.[2] This system is located at a distance of 247 light years from the Sun based on parallax measurements,[1] but is drifting closer with a radial velocity of –7.0 km/s.[4]

HD 134064
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes
Right ascension 15h 07m 20.369s[1]
Declination +18° 26′ 30.57″[1]
Apparent magnitude (V) 6.03[2]
Characteristics
Spectral type A3Vnn[2]
U−B color index +0.06[3]
B−V color index +0.06[3]
Astrometry
Radial velocity (Rv)–7.0[4] km/s
Proper motion (μ) RA: +42.368 mas/yr[1]
Dec.: −49.682 mas/yr[1]
Parallax (π)13.2096 ± 0.0324 mas[1]
Distance246.9 ± 0.6 ly
(75.7 ± 0.2 pc)
Orbit[5]
Period (P)8.0 yr
Semi-major axis (a)0.10″
Eccentricity (e)0.45
Inclination (i)122.6°
Longitude of the node (Ω)41.3°
Periastron epoch (T)B 1939.97
Argument of periastron (ω)
(secondary)
71.4°
Details
HD 134064 A
Mass2.15[6] M
Luminosity16[7] L
Surface gravity (log g)4.25[6] cgs
Temperature9,732±331[6] K
Rotational velocity (v sin i)185[6] km/s
Age160[6] Myr
HD 134064 B
Mass0.73[8] M
Other designations
BD+19° 2924, HD 134064, HIP 74000, HR 5633, SAO 101379, WDS J15073+1827AB[9]
Database references
SIMBADdata

The components of this system are orbiting each other with a period of eight years and a high orbital eccentricity of 0.45.[5] The pair are separated by an orbital distance of around 8,000 AU.[8] The primary component is a rapidly rotating A-type main sequence star with a stellar classification of A3Vnn.[2] It has 2.15 times the mass of the Sun and is spinning with a projected rotational velocity of 185 km/s.[6] The secondary star has 73% of the Sun's mass.[8] The system is young, with an estimated age of 160 million years.[6]

References

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  1. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  2. ^ a b c d Paunzen, E.; et al. (July 2001), "A spectroscopic survey for λ Bootis stars. II. The observational data", Astronomy and Astrophysics, 373 (2): 625–632, Bibcode:2001A&A...373..625P, doi:10.1051/0004-6361:20010630.
  3. ^ a b Osawa, Kiyoteru (July 1959), "Spectral Classification of 533 B8-A2 Stars and the Mean Absolute Magnitude of a0 V Stars", Astrophysical Journal, 130: 159, Bibcode:1959ApJ...130..159O, doi:10.1086/146706.
  4. ^ a b Kharchenko, N. V.; et al. (2007), "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ˜55000 stars and mean radial velocities of 516 Galactic open clusters and associations", Astronomische Nachrichten, 328 (9): 889–896, arXiv:0705.0878, Bibcode:2007AN....328..889K, doi:10.1002/asna.200710776, S2CID 119323941.
  5. ^ a b "Sixth Catalog of Orbits of Visual Binary Stars", United States Naval Observatory, archived from the original on 1 August 2017, retrieved 21 May 2017.
  6. ^ a b c d e f g 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, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
  7. ^ McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
  8. ^ a b c De Rosa, R. J.; et al. (January 2014), "The VAST Survey - III. The multiplicity of A-type stars within 75 pc", Monthly Notices of the Royal Astronomical Society, 437 (2): 1216–1240, arXiv:1311.7141, Bibcode:2014MNRAS.437.1216D, doi:10.1093/mnras/stt1932, S2CID 88503488.
  9. ^ "HD 134064", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2024-04-15.
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