Xi Columbae

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Xi Columbae
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Columba
Right ascension 05h 55m 29.91727s[1]
Declination −37° 07′ 14.4156″[1]
Apparent magnitude (V) 4.97[2]
Characteristics
Spectral type K1 III CNII[3]
B−V color index +1.096[2]
Astrometry
Radial velocity (Rv) +59.5[4] km/s
Proper motion (μ) RA: +36.90[1] mas/yr
Dec.: −25.35[1] mas/yr
Parallax (π) 9.80 ± 0.37[1] mas
Distance 330 ± 10 ly
(102 ± 4 pc)
Absolute magnitude (MV) −0.05[5]
Orbit[5]
Period (P) 1420.6 d
Semi-major axis (a) 3.60 AU
Eccentricity (e) 0.39
Semi-amplitude (K1)
(primary)
5.68 km/s
Details
Luminosity 132[6] L
Surface gravity (log g) 2.26[2] cgs
Temperature 4,659[2] K
Metallicity [Fe/H] +0.29[2] dex
Rotational velocity (v sin i) 2.6[5] km/s
Other designations
ξ Col, CD−37° 2487, HD 40176, HIP 28010, HR 2087, SAO 196316.[7]
Database references
SIMBAD data

Xi Columbae is a binary star[5] system in the southern constellation of Columba. With an apparent visual magnitude of 4.97,[2] it is faintly visible to the naked eye. To ancient Arabian astronomers, this star, along with ζ CMa, λ CMa, γ Col, δ Col, θ Col, κ Col, λ Col and μ Col, formed Al Ḳurūd (ألقرد - al-qird), the Apes.[8] Based upon an annual parallax shift of 9.80 mas,[1] it is located around 330 light years from the Sun.

This is an astrometric binary[9] with an orbital period of 1,420.6 days and an eccentricity of 0.39.[5] The primary is an evolved K-type giant star with a stellar classification of K1 III CNII.[3] It is a member of the HR 1614 supergroup[10] and shows an overabundance of CN.[3] The companion has a mass of at least 59% that of the Sun.[5]

References[edit]

  1. ^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752Freely accessible, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357. 
  2. ^ a b c d e f Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal, 150 (3): 23, arXiv:1507.01466Freely accessible, Bibcode:2015AJ....150...88L, doi:10.1088/0004-6256/150/3/88, 88. 
  3. ^ a b c Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1982MSS...C03....0H. 
  4. ^ Wilson, Ralph Elmer (1953), General Catalogue of Stellar Radial Velocities, Washington: Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W. 
  5. ^ a b c d e f Setiawan, J.; et al. (July 2004), "Precise radial velocity measurements of G and K giants. Multiple systems and variability trend along the Red Giant Branch", Astronomy and Astrophysics, 421: 241−254, Bibcode:2004A&A...421..241S, doi:10.1051/0004-6361:20041042-1. 
  6. ^ 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:1208.2037Freely accessible, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x. 
  7. ^ "ksi Col -- Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2016-12-31. 
  8. ^ Davis Jr., G. A. (October 1944), "The Pronunciations, Derivations, and Meanings of a Selected List of Star Names", Popular Astronomy, 18: 14, Bibcode:1944PA.....52....8D. 
  9. ^ 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:0806.2878Freely accessible, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x. 
  10. ^ Eggen, Olin J. (August 1997), "The Abundance of CN, Calcium and Heavy Elements in High Velocity Stars.", The Astronomical Journal, 114: 825−836, Bibcode:1997AJ....114..825E, doi:10.1086/118516.