Astronomy:HD 165189

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Short description: Star in the constellation Corona Australis
HD 165189
Observation data
Equinox J2000.0]] (ICRS)
Constellation Corona Australis
Right ascension  18h 06m 49.89282s[1]
Declination −43° 25′ 30.8022″[1]
Apparent magnitude (V) 4.92[2]
Characteristics
Spectral type A6 V + A7 V[3]
B−V color index 0.255±0.017[2]
Astrometry
Radial velocity (Rv)−7.80±0.40[2] km/s
Proper motion (μ) RA: +10.990[1] mas/yr
Dec.: −105.742[1] mas/yr
Parallax (π)22.4417 ± 0.1608[1] mas
Distance145 ± 1 ly
(44.6 ± 0.3 pc)
Absolute magnitude (MV)1.81[2]
Orbit[4]
Period (P)450.0 yr
Semi-major axis (a)2.04″
Eccentricity (e)0.650
Inclination (i)123.1°
Longitude of the node (Ω)85.8°
Periastron epoch (T)1854.7
Argument of periastron (ω)
(secondary)
282.7°
Details
HD 165189
Mass1.59[5] M
Luminosity36.4+6.4
−5.2
[6] L
Temperature7,745+53
−46
[6] K
Rotational velocity (v sin i)104[7] km/s
HD 165190
Mass1.58[5] M
Other designations
CD−43°12272, GC 24649, HIP 88726, CCDM J18068-4325, WDS J18068-4325[8]
HD 165189: HR 6749
HD 165190: HR 6750
Database references
SIMBADdata

HD 165189 and HD 165190 are components of a visual binary star[5] system located 145[1] light years away in the southern constellation of Corona Australis. It is visible to the naked eye with the primary having an apparent visual magnitude of 4.929±0.025. The system is a member of the Beta Pictoris Moving Group.[3]

The pair orbit each other with a period of 450 years and a large eccentricity of 0.650.[4] They have a projected separation of 70.1 astronomical unit|AU.[5] Both components are A-type main-sequence stars; the primary has a stellar classification of A6 V while the secondary is A7 V.[3] They have similar masses of 1.59 and 1.58 times the mass of the Sun, respectively.[5]

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. 
  2. 2.0 2.1 2.2 2.3 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 3.2 Bell, Cameron P. M. et al. (November 2015), "A self-consistent, absolute isochronal age scale for young moving groups in the solar neighbourhood", Monthly Notices of the Royal Astronomical Society 454 (1): 593–614, doi:10.1093/mnras/stv1981, Bibcode2015MNRAS.454..593B. 
  4. 4.0 4.1 Alzner, A.; Argyle, R. (June 2001), "New orbits for WDS 05248-5219, WDS 18068-4325", IAU Commission 26. (Double Stars) Information Circular 144: 1–2, Bibcode2001IAUDS.144R...1A. 
  5. 5.0 5.1 5.2 5.3 5.4 Tokovinin, A.; Kiyaeva, O. (February 2016), "Eccentricity distribution of wide binaries", Monthly Notices of the Royal Astronomical Society 456 (2): 2070–2079, doi:10.1093/mnras/stv2825, Bibcode2016MNRAS.456.2070T. 
  6. 6.0 6.1 Zorec, J. et al. (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. Royer, F.; Gerbaldi, M.; Faraggiana, R.; Gómez, A. E. (January 2002), "Rotational velocities of A-type stars. I. Measurement of v sin i in the southern hemisphere", Astronomy and Astrophysics 381: 105–121, doi:10.1051/0004-6361:20011422, Bibcode2002A&A...381..105R. 
  8. "CD-43 12272". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=CD-43+12272.