Kappa Virginis

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κ Volantis
Virgo IAU.svg
Cercle rouge 100%.svg

Location of κ Virginis
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Virgo
Right ascension 14h 12m 53.74538s[1]
Declination −10° 16′ 25.3340″[1]
Apparent magnitude (V) 4.180[2]
Characteristics
Spectral type K2/3 III[3]
U−B color index +1.457[2]
B−V color index +1.343[2]
Astrometry
Radial velocity (Rv) −4.38±0.21[4] km/s
Proper motion (μ) RA: +7.25[1] mas/yr
Dec.: +139.88[1] mas/yr
Parallax (π) 12.80 ± 0.25[1] mas
Distance 255 ± 5 ly
(78 ± 2 pc)
Details
Mass 1.46±0.04[5] M
Radius 25.41±0.74[5] R
Luminosity 229[5] L
Surface gravity (log g) 1.83±0.08[5] cgs
Temperature 4235±20[5] K
Metallicity [Fe/H] 0.43±0.04[5] dex
Rotational velocity (v sin i) 5.1[4] km/s
Age 9.67±0.97[5] Gyr
Other designations
98 Virginis, κ Vir, BD−09° 3878, FK5 523, HD 124294, HIP 69427, HR 5315, SAO 158427.[6]
Database references
SIMBAD data

Kappa Virginis (κ Vir, κ Virginis) is a solitary star in the zodiac constellation of Virgo. It has an apparent visual magnitude of 4.18,[2] which is sufficiently bright to be seen with the naked eye. Based upon stellar parallax measurements, the distance to this star is about 255 light years.

This is an orange-hued K-type giant star with a stellar classification of K2/3 III.[3] It has about 146% of the mass of the Sun, but at an estimated age of 9.7 billion years it has evolved and expanded to over 25 times the Sun's radius. As a consequence, it shines with around 229 times the solar luminosity. The effective temperature of the star's outer atmosphere is 4,235 K.[5]

References[edit]

  1. ^ a b c d e van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752Freely accessible, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357. 
  2. ^ a b c d Jennens, P. A.; Helfer, H. L. (September 1975), "A new photometric metal abundance and luminosity calibration for field G and K giants.", Monthly Notices of the Royal Astronomical Society, 172: 667–679, Bibcode:1975MNRAS.172..667J, doi:10.1093/mnras/172.3.667. 
  3. ^ a b Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Bibcode:1999MSS...C05....0H. 
  4. ^ a b Massarotti, Alessandro; et al. (January 2008), "Rotational and radial velocities for a sample of 761 HIPPARCOS giants and the role of binarity", The Astronomical Journal, 135 (1): 209–231, Bibcode:2008AJ....135..209M, doi:10.1088/0004-6256/135/1/209. 
  5. ^ a b c d e f g h Maldonado, J.; et al. (June 2013), "The metallicity signature of evolved stars with planets", Astronomy & Astrophysics, 554: 18, arXiv:1303.3418Freely accessible, Bibcode:2013A&A...554A..84M, doi:10.1051/0004-6361/201321082, A84. 
  6. ^ "kap Vir -- Variable Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2016-09-08.