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89 Aquarii

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89 Aquarii
Diagram showing star positions and boundaries of the Aquarius constellation and its surroundings
Location of 89 Aquarii (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Aquarius
Right ascension 23h 09m 54.89736s[1]
Declination –22° 27′ 27.4192″[1]
Apparent magnitude (V) 4.69[2]
Characteristics
Spectral type G3 II A2 V[3]
U−B color index 0.39[2]
B−V color index 0.65[2]
Astrometry
Radial velocity (Rv)-4.8[4] km/s
Proper motion (μ) RA:  32.61[1] mas/yr
Dec.: –9.76[1] mas/yr
Parallax (π)6.47 ± 0.68 mas[1]
Distanceapprox. 500 ly
(approx. 150 pc)
Absolute magnitude (MV)0.1/1.5[5]
Details
89 Aqr A
Mass2.9[5] M
Surface gravity (log g)3.62[6] cgs
Temperature5,640[6] K
Metallicity [Fe/H] 0.27[6] dex
Age320[5] Myr
89 Aqr B
Mass2.0[5] M
Temperature8,912[5] K
Other designations
CD–23 17771, HIP 114375, HR 8817, SAO 191687.[7]
89 Aqr A: HD 218640.
89 Aqr B: HD 218641.
Database references
SIMBADdata

89 Aquarii (abbreviated 89 Aqr) is a binary star[3] system in the equatorial constellation of Aquarius. 89 Aquarii is the Flamsteed designation, though it also bears the Bayer designation c3 Aquarii.[8] The apparent visual magnitude of 4.69[2] is bright enough to be seen with the naked eye. Its distance from Earth is roughly 500 light-years (150 pc), based upon parallax measurements with an 11% margin of error.[1]

The primary component of this system has a magnitude of 5.27 and a stellar classification of G3 II, which suggests this is an evolved star in the bright giant stage. The companion is an A-type main sequence star with a stellar classification of A2 V.[3] As of 2010, it is located at an angular separation of 0.1843 arcseconds along a position angle of 135.1°.[9] They orbit each other with an estimated period of 201 years and a semimajor axis of 0.45 arcseconds.[5]

References

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  1. ^ a b c d e f van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
  2. ^ a b c d Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series, 34: 1–49, Bibcode:1978A&AS...34....1N.
  3. ^ a b c 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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  4. ^ Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Carnegie Institute of Washington, D.C., Bibcode:1953GCRV..C......0W.
  5. ^ a b c d e f Parsons, Sidney B. (May 2004), "New and Confirmed Triple Systems with Luminous Cool Primaries and Hot Companions", The Astronomical Journal, 127 (5): 2915–2930, Bibcode:2004AJ....127.2915P, doi:10.1086/383546.
  6. ^ a b c McWilliam, Andrew (December 1990), "High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances", Astrophysical Journal Supplement Series, 74: 1075–1128, Bibcode:1990ApJS...74.1075M, doi:10.1086/191527.
  7. ^ "* 89 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-07-13.
  8. ^ [1] database record, HD-DM-GC-HR-HIP-Bayer-Flamsteed Cross Index, N. D. Kostjuk, Institute of Astronomy of Russian Academy of Sciences, 2002; CDS ID IV/27A.
  9. ^ Tokovinin, A.; et al. (December 2010), "High-Resolution Imaging at the SOAR Telescope", Publications of the Astronomical Society of the Pacific, 122 (898): 1483–1494, arXiv:1010.4176, Bibcode:2010PASP..122.1483T, doi:10.1086/657903, S2CID 26826524.
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