Gamma Cancri

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Gamma Cancri
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Cancer
Right ascension 08h 43m 17.14820s[1]
Declination +21° 28′ 06.6008″[1]
Apparent magnitude (V) 4.652[2]
Characteristics
Spectral type A1IV[2]
U−B color index +0.03[3]
B−V color index +0.00[3]
Astrometry
Radial velocity (Rv) 28.7[4] km/s
Proper motion (μ) RA: -103.51[1] mas/yr
Dec.: -39.48[1] mas/yr
Parallax (π) 18.00 ± 0.21[1] mas
Distance 181 ± 2 ly
(55.6 ± 0.6 pc)
Absolute magnitude (MV) +1.1[5]
Details
Radius 2.5[6] R
Temperature 8800[7] K
Rotational velocity (v sin i) 86 ± 6[8] km/s
Other designations
Gamma Cancri, Asellus Borealis, 43 Cancri, HR 3449, HD 74198, BD+21°1895, FK5 1228, HIP 42806, SAO 80378, GC 11982, CCDM 08433+2128
Database references
SIMBAD data

Gamma Cancri (γ Cancri, abbreviated Gamma Cnc, γ Cnc), also named Asellus Borealis,[9] is a star in the constellation of Cancer.

Since it is near the ecliptic, it can be occulted by the Moon and, very rarely, by planets.

Nomenclature[edit]

γ Cancri (Latinised to Gamma Cancri) is the star's Bayer designation.

It bore the traditional name Asellus Borealis (Latin for "northern donkey colt"). In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[10] to catalogue and standardize proper names for stars. The WGSN approved the name Asellus Borealis for this star on 6 November 2016 and it is now so entered in the IAU Catalog of Star Names.[9]

In Chinese, 鬼宿 (Guǐ Su), meaning Ghost, refers to an asterism consisting of Gamma Cancri, Theta Cancri, Eta Cancri and Delta Cancri.[11] Consequently, Gamma Cancri itself is known as 鬼宿三 (Guǐ Su sān, English: the Third Star of Ghost.)[12]

Properties[edit]

Gamma Cancri is a white A-type subgiant with an apparent magnitude of +4.67. [2] Located around 181 light-years from the Sun, it shines with a luminosity approximately 35 times greater and has a surface temperature of 9108 K.[13]

References[edit]

  1. ^ a b c d e van Leeuwen, F. (2007). "Validation of the New Hipparcos Reduction". Astronomy and Astrophysics. 474 (2): 653–64. Bibcode:2007A&A...474..653V. arXiv:0708.1752Freely accessible. doi:10.1051/0004-6361:20078357. 
  2. ^ a b c "gam Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 8 April 2015. 
  3. ^ a b Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Bibcode:1986EgUBV........0M. 
  4. ^ Wilson, Ralph Elmer (1953). "General catalogue of stellar radial velocities". Bibcode:1953GCRV..C......0W. 
  5. ^ Eggen, O. J.; Iben, Icko, Jr. (1988). "Starbursts, binary stars, and blue stragglers in local superclusters and groups. I - The very young disk and young disk populations". Astronomical Journal. 96: 635–669. Bibcode:1988AJ.....96..635E. doi:10.1086/114834. 
  6. ^ Pasinetti Fracassini, L. E.; et al. (2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics". Astronomy & Astrophysics. 367: 521–24. Bibcode:2001A&A...367..521P. arXiv:astro-ph/0012289Freely accessible. doi:10.1051/0004-6361:20000451. 
  7. ^ Theodossiou, E.; Danezis, E. (1991). "The stellar temperature scale for stars of spectral types from O8 to F6 and the standard deviation of the MK spectral classification". Astrophysics and Space Science. 183 (1): 91–115. Bibcode:1991Ap&SS.183...91T. doi:10.1007/BF00643019. 
  8. ^ Royer, F.; Grenier, S.; Baylac, M.-O.; Gómez, A. E.; Zorec, J. (2002). "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i". Astronomy and Astrophysics. 393: 897–911. Bibcode:2002A&A...393..897R. arXiv:astro-ph/0205255Freely accessible. doi:10.1051/0004-6361:20020943. 
  9. ^ a b "IAU Catalog of Star Names". Retrieved 21 November 2016. 
  10. ^ IAU Working Group on Star Names (WGSN), International Astronomical Union, retrieved 22 May 2016. 
  11. ^ (in Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
  12. ^ (in Chinese) 香港太空館 - 研究資源 - 亮星中英對照表 Archived August 11, 2010, at the Wayback Machine., Hong Kong Space Museum. Accessed on line November 23, 2010.
  13. ^ McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012). "Fundamental Parameters and Infrared Excesses of Hipparcos Stars". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–57. Bibcode:2012MNRAS.427..343M. arXiv:1208.2037Freely accessible. doi:10.1111/j.1365-2966.2012.21873.x.