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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
SIMBAD data

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]

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

  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.

External links