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Gamma Chamaeleontis is a solitary[9] star located in the southern circumpolar constellation of Chamaeleon. Its name is a Bayer designation that is Latinized from γ Chamaeleontis, and abbreviated Gamma Cha or γ Cha. This star can faintly be seen with the naked eye on a dark night, having an apparent visual magnitude of 4.12.[3] Based upon an annual parallax shift of 7.35 mas,[2] it is located around 444 light-years (136 pc) from the Sun. This star is drifting closer with a line of sight velocity component of −22 km/s.[5]

This is an evolved K-type giant star with a stellar classification of K5 III.[4] It is a suspected variable star, with an amplitude of 0.01 magnitude.[10] With 78 times the radius of the Sun,[2] this star radiates 864[6] times the solar luminosity from its enlarged outer atmosphere at an effective temperature of 3,870 K.[7]

References

  1. 1 2 3 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015 XHIP record for this object at VizieR.
  2. 1 2 3 4 5 6 7 8 Vallenari, A.; et al. (Gaia collaboration) (2023), "Gaia Data Release 3. Summary of the content and survey properties", Astronomy and Astrophysics, 674: A1, arXiv:2208.00211, Bibcode:2023A&A...674A...1G, doi:10.1051/0004-6361/202243940, S2CID 244398875 Gaia DR3 record for this source at VizieR.
  3. 1 2 3 Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M.
  4. 1 2 Houk, N.; Cowley, A. P. (1975), "Catalogue of two-dimensional spectral types for the HD stars", University of Michigan, I, Bibcode:1975mcts.book.....H.
  5. 1 2 Wielen, R.; et al. (1999), "Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions", Veröff. Astronomisches Rechen-Institut Heidelb, 35 (35), Astronomisches Rechen-Institut Heidelberg: 1, Bibcode:1999VeARI..35....1W.
  6. 1 2 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.
  7. 1 2 3 4 5 Borisov, S. B.; et al. (2023), "New Generation Stellar Spectral Libraries in the Optical and Near-infrared. I. The Recalibrated UVES-POP Library for Stellar Population Synthesis", The Astrophysical Journal Supplement Series, 266 (1): 11, arXiv:2211.09130, Bibcode:2023ApJS..266...11B, doi:10.3847/1538-4365/acc321.
  8. "gam Cha", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2016-12-11.
  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:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  10. Eggen, O. J. (1973), "The classification of intrinsic variables. IV. Very-small-amplitude, very-short-period red variables", Astrophysical Journal, 184: 793, Bibcode:1973ApJ...184..793E, doi:10.1086/152371.

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