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22 Camelopardalis

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22 Camelopardalis
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Camelopardalis
Right ascension 05h 39m 05.40416s[1]
Declination +56° 21′ 36.1540″[1]
Apparent magnitude (V) 7.03[2]
Characteristics
Spectral type F5 V[3]
B−V color index 0.411±0.004[2]
Astrometry
Radial velocity (Rv)+10.3±1.8[4] km/s
Proper motion (μ) RA: +10.514[1] mas/yr
Dec.: −131.789[1] mas/yr
Parallax (π)15.4048 ± 0.1014 mas[1]
Distance212 ± 1 ly
(64.9 ± 0.4 pc)
Absolute magnitude (MV)3.14[3]
Orbit[5]
Period (P)81.463±0.005 d
Eccentricity (e)0.136±0.024
Periastron epoch (T)51969.9±2.2 MJD
Argument of periastron (ω)
(secondary)
0±10°
Semi-amplitude (K1)
(primary)
9.52±0.24 km/s
Details
Mass1.34[6] M
Radius1.68[1] R
Luminosity5.215[1] L
Surface gravity (log g)4.26[6] cgs
Temperature6,732±229[6] K
Metallicity [Fe/H]0.01[4] dex
Age1.515[6] Gyr
Other designations
22 Cam, BD+56°1044, GC 6990, HD 37070, HIP 26587, SAO 25298[7]
Database references
SIMBADdata

22 Camelopardalis is a binary star system in the northern circumpolar constellation of Camelopardalis,[7] located 212 light years away from the Sun.[1] It has an apparent visual magnitude of 7.03,[2] which is below the normal limit for visibility with the naked eye. This object is moving further from the Earth with a mean heliocentric radial velocity of +10 km/s.[4] Eggen (1991) listed it as a member of the IC 2391 supercluster.[8] It has also been catalogued as a member of the Hyades group. However, Griffin (2005) suggests it belongs to neither.[5]

This is a single-lined spectroscopic binary system with an orbital period of 81.5 days and a significant eccentricity of 0.14. It has an 'a sin i' value of 10.57 ± 0.27 Gm (0.0707 ± 0.0018 AU),[5] where a is the semimajor axis and i is the orbital inclination to the line of sight from the Earth. This value provides a lower bound on the true semimajor axis of their orbit.

The visible component is an F-type main-sequence star with a stellar classification of F5 V.[3] It is an estimated 1.5[6] billion years old with 1.3[6] times the mass of the Sun and 1.7[1] times the Sun's radius. It is radiating 5.2[1] times the Sun's luminosity from its photosphere at an effective temperature of 6,732 K.[6]

References

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  1. ^ a b c d e f g h i j Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c 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, S2CID 119257644.
  3. ^ a b c Abt, Helmut A. (2004), "Spectral Classification of Stars in A Supplement to the Bright Star Catalogue", The Astrophysical Journal Supplement Series, 155 (1): 175–177, Bibcode:2004ApJS..155..175A, doi:10.1086/423803
  4. ^ a b c Casagrande, L.; et al. (June 2011), "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey", Astronomy and Astrophysics, 530: A138, arXiv:1103.4651, Bibcode:2011A&A...530A.138C, doi:10.1051/0004-6361/201016276, S2CID 56118016.
  5. ^ a b c Griffin, R. F. (June 2005), "Spectroscopic binary orbits from photoelectric radial velocities. Paper 182: 22 Camelopardalis, HD 156051, HR 6890, & HD 221757", The Observatory, 125: 134–152, Bibcode:2005Obs...125..134G.
  6. ^ a b c d e f g 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, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
  7. ^ a b "22 Cam". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-04-17.
  8. ^ Eggen, O. J. (December 1991), "The IC 2391 Supercluster", Astronomical Journal, 102: 2028, Bibcode:1991AJ....102.2028E, doi:10.1086/116025.