Astronomy:23 Comae Berenices

From HandWiki
Short description: Binary star system in the constellation Coma Berenices
23 Comae Berenices
Map of the constellation Coma Berenices
23 Comae Berenices (circled) in the constellation Coma Berenices
Observation data
Equinox J2000.0]] (ICRS)
Constellation Coma Berenices
Right ascension  12h 34m 51.08058s[1]
Declination +22° 37′ 45.3303″[1]
Apparent magnitude (V) 4.80[2] (4.96 + 6.90)[3]
Characteristics
Spectral type A0IV[4]
U−B color index −0.01[5]
B−V color index +0.012±0.015[2]
Astrometry
Radial velocity (Rv)−16.0±1.8[6] km/s
Proper motion (μ) RA: −58.89[1] mas/yr
Dec.: 28.31[1] mas/yr
Parallax (π)10.52 ± 0.52[1] mas
Distance310 ± 20 ly
(95 ± 5 pc)
Absolute magnitude (MV)−0.08[2]
Orbit[7]
Period (P)33.04 yr
Semi-major axis (a)0.219″
Eccentricity (e)0.898
Inclination (i)109.7°
Longitude of the node (Ω)24.3°
Periastron epoch (T)B1964.62
Argument of periastron (ω)
(secondary)		214.5°
Details
Mass2.15[8] M☉
Radius3.0[9] R☉
Luminosity104.00[2] L☉
Surface gravity (log g)3.85[8] cgs
Temperature9,675±329[8] K
Rotational velocity (v sin i)40[8] km/s
Age210[8] Myr
Other designations
Phyllon Kissinou, 23 Com, BD+23°2475, FK5 1323, GC 17142, HD 109485, HIP 61394, HR 4789, SAO 82390, WDS J12349+2238[10]
Database references
SIMBADdata

23 Comae Berenices, also named Phyllon Kissinou,[11] is a binary star[7] system in the northern constellation of Coma Berenices, situated a few degrees away from the North Galactic Pole.[12] It is visible to the naked eye as a faint, white-hued point of light with an apparent visual magnitude of 4.80.[2] The system is located around 310 light years away from the Sun, based on parallax.[1] It is moving closer to the Earth with a heliocentric radial velocity of −16 km/s.[6]

The components of this system orbit each other with a period of 33 years, a large eccentricity of 0.9, and an angular semimajor axis of 0.219″.[7] The primary, designated component A, is a magnitude 4.96[3] star with a stellar classification of A0IV,[4] matching an A-type subgiant that has exhausted the supply of hydrogen at its core and is in the process of evolving into a giant. Bychkov et al. (2009) list it as an Am star with an average field strength of 26×10−4 T.[13]

The primary is 210[8] million years old and is spinning with a projected rotational velocity of 40 km/s.[8] It has 2.15[8] times the mass of the Sun and about three[9] times the Sun's radius. The star is radiating 104[2] times the luminosity of the Sun from its photosphere at an effective temperature of 9,675 K.[8]

In Ptolemy's Almagest, this star is described as "shaped like an ivy leaf" (φύλλοv κισσίνου, phyllon kissinou), presumably referring to the overall shape of the Coma Star Cluster.[14] Based on this, some modern sources have referred to it as Kissin (or Kissīn); this name has also been used for 21 Comae Berenices.[15] The IAU Working Group on Star Names approved the name Phyllon Kissinou for this star on 16 May 2024 and it is now so entered in the IAU Catalog of Star Names;[11] since this is a binary system, the IAU has mentioned that the names Phyllon and Kissinou can be applied to the primary and secondary components, respectively.[16]

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode: 2007A&A...474..653V. 
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A. 
  3. ↑ 3.0 3.1 Malkov, O. Yu.; Tamazian, V. S.; Docobo, J. A.; Chulkov, D. A. (2012). "Dynamical Masses of a Selected Sample of Orbital Binaries". Astronomy and Astrophysics 546: 5. doi:10.1051/0004-6361/201219774. A69. Bibcode: 2012A&A...546A..69M. 
  4. ↑ 4.0 4.1 Cowley, A.; Cowley, C.; Jaschek, M.; Jaschek, C. (April 1969). "A study of the bright A stars. I. A catalogue of spectral classifications". Astronomical Journal 74: 375–406. doi:10.1086/110819. Bibcode: 1969AJ.....74..375C. 
  5. ↑ Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode: 1986EgUBV........0M. 
  6. ↑ 6.0 6.1 de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics 546: 14, doi:10.1051/0004-6361/201219219, A61, Bibcode: 2012A&A...546A..61D. 
  7. ↑ 7.0 7.1 7.2 Seymour, Diana M.; Mason, Brian D.; Hartkopf, William I.; Wycoff, Gary L. (February 2002), "Binary Star Orbits. II. Preliminary First Orbits for 117 Systems", The Astronomical Journal 123 (2): 1023–1038, doi:10.1086/338441, Bibcode: 2002AJ....123.1023S. 
  8. ↑ 8.0 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 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. doi:10.1088/0004-637X/804/2/146. Bibcode: 2015ApJ...804..146D. 
  9. ↑ 9.0 9.1 Pasinetti Fracassini, L. E. et al. (February 2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)". Astronomy and Astrophysics 367 (2): 521–524. doi:10.1051/0004-6361:20000451. Bibcode: 2001A&A...367..521P. 
  10. ↑ "23 Com". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=23+Com. 
  11. ↑ 11.0 11.1 "IAU Catalog of Star Names". https://exopla.net/star-names/modern-iau-star-names/. 
  12. ↑ Straizys, V.; Meistas, E. (1989). "Photoelectric photometry of bright stars in the vicinity of the North Galactic Pole". Vilnius Astronomijos Observatorijos Biuletenis 84: 26. Bibcode: 1989VilOB..84...26S. 
  13. ↑ Bychkov, V. D. et al. (2009), "Catalogue of averaged stellar effective magnetic fields - II. Re-discussion of chemically peculiar A and B stars", Monthly Notices of the Royal Astronomical Society 394 (3): 1338, doi:10.1111/j.1365-2966.2008.14227.x, Bibcode: 2009MNRAS.394.1338B. 
  14. ↑ Ridpath, Ian. "Star Tales - Coma Berenices". http://ianridpath.com/startales/comaberenices.html. 
  15. ↑ Allen, Richard Hinckley (1963), Star Names: Their Lore and Meaning, Dover Publications Inc., p. 171, https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Coma_Berenices*.html, retrieved 2019-11-01. 
  16. ↑ IAU Working Group on Star Names. Annual Report 2024 (Report). https://exopla.net/wp-content/uploads/2025/04/2024_Annual-Report-WGSN_for2024.pdf. 



Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:23_Comae_Berenices&oldid=3937403"