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ε Corvi
Corvus constellation map.svg
Red circle.svg
Location of ε Corvi (circled)
Observation data
Epoch J2000       Equinox J2000
Constellation Corvus
Right ascension 12h 10m 07.48058s [1]
Declination –22° 37′ 11.1620″ [1]
Apparent magnitude (V) +3.024 [2]
Characteristics
Spectral type K2 III [3]
U−B color index +1.458 [2]
B−V color index +1.318 [2]
Astrometry
Radial velocity (Rv)+4.9 [4] km/s
Proper motion (μ) RA: –71.74  mas/ yr
Dec.: +10.25  mas/ yr
Parallax (π)10.26 ± 0.16  mas [1]
Distance318 ± 5  ly
(97 ± 2  pc)
Absolute magnitude (MV)−1.82+0.15
−0.14
[5]
Details
Mass3.2 [6]  M
Radius52 [7]  R
Surface gravity (log g)2.16 [8]  cgs
Temperature4320 [8]  K
Metallicity [Fe/H]–0.13 [8]  dex
Rotational velocity (v sin i)1.0 [6] km/s
Other designations
2 Crv, BD−21° 3487, FK5 453, HD 105707, HIP 59316, HR 4630, SAO 180531. [9]
Database references
SIMBAD data

Epsilon Corvi (ε Crv, ε Corvi) is a star in the southern constellation of Corvus. It has the traditional name Minkar /ˈmɪŋkɑːr/, from Arabic منقار minqar meaning "beak [of the crow]" [10] The apparent visual magnitude is +3.0 [2] and it is located at a distance of 318 light-years (97 parsecs) from Earth. [1]

In Chinese, 軫宿 (Zhěn Sù), meaning Chariot (asterism), refers to an asterism consisting of ε Corvi, γ Corvi, δ Corvi and β Corvi. [11] Consequently, ε Corvi itself is known as 軫宿二 (Zhěn Sù èr, English: the Second Star of Chariot.). [12]

Epsilon Corvi is a red giant with a stellar classification of K2 III, having consumed the hydrogen at its core and evolved away from the main sequence. It has about three times the Sun's mass. [6] The interferometry-measured angular diameter of this star is about 4.99  mas, [13] which, at its estimated distance, equates to a physical radius of about 52 times the radius of the Sun. [7] The effective temperature of the outer envelope is 4320 K, [8] giving it an orange hue that is characteristic of a K-type star. [14] Around 4 times as massive as the Sun, it spent much of its life as a main sequence star of spectral type B5V. [15]

References

  1. ^ a b c d van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv: 0708.1752, Bibcode: 2007A&A...474..653V, doi: 10.1051/0004-6361:20078357, S2CID  18759600
  2. ^ a b c d Celis S., L. (October 1975), "Photoelectric photometry of late-type variable stars", Astronomy and Astrophysics Supplement Series, 22: 9–17, Bibcode: 1975A&AS...22....9C
  3. ^ Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 4, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode: 1988mcts.book.....H
  4. ^ Wielen, R.; et al. (1999), "Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions", Veroeffentlichungen des Astronomischen Rechen-Instituts Heidelberg, Astronomisches Rechen-Institut Heidelberg, 35 (35): 1, Bibcode: 1999VeARI..35....1W
  5. ^ Carney, Bruce W.; et al. (March 2008), "Rotation and Macroturbulence in Metal-Poor Field Red Giant and Red Horizontal Branch Stars", The Astronomical Journal, 135 (3): 892–906, arXiv: 0711.4984, Bibcode: 2008AJ....135..892C, doi: 10.1088/0004-6256/135/3/892, S2CID  2756572
  6. ^ a b c Melo, C. H. F.; et al. (August 2005), "On the nature of lithium-rich giant stars. Constraints from beryllium abundances", Astronomy and Astrophysics, 439 (1): 227–235, arXiv: astro-ph/0504133, Bibcode: 2005A&A...439..227M, doi: 10.1051/0004-6361:20041805, S2CID  10580797
  7. ^ a b Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3rd ed.), Birkhäuser, ISBN  3-540-29692-1. The radius (R*) is given by:
  8. ^ a b c d McWilliam, Andrew (December 1990), "High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances", Astrophysical Journal Supplement Series, 74: 1075–1128, Bibcode: 1990ApJS...74.1075M, doi: 10.1086/191527
  9. ^ "MINKAR -- Variable Star", SIMBAD, Centre de Données astronomiques de Strasbourg, retrieved 2012-01-23
  10. ^ Al-Sufi, Book Of Fixed Stars, Constellation: The Crow
  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 January 30, 2011, at the Wayback Machine, Hong Kong Space Museum. Accessed on line November 23, 2010.
  13. ^ Richichi, A.; Percheron, I.; Khristoforova, M. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics, 431 (2): 773–777, Bibcode: 2005A&A...431..773R, doi: 10.1051/0004-6361:20042039
  14. ^ "The Colour of Stars", Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived from the original on 2012-03-18, retrieved 2012-01-16
  15. ^ Kaler, James B. (Jim), "Minkar", Stars, University of Illinois, retrieved 12 July 2015