Nu Virginis

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ν Virginis
Virgo IAU.svg
Cercle rouge 100%.svg

Location of ν Virginis
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Virgo
Right ascension 11h 45m 51.55957s[1]
Declination +06° 31′ 45.7413″[1]
Apparent magnitude (V) 4.04[2]
Characteristics
Spectral type M1 III[3]
U−B color index +1.80[2]
B−V color index +1.52[2]
Astrometry
Radial velocity (Rv) 50.19±0.30[4] km/s
Proper motion (μ) RA: −18.96[1] mas/yr
Dec.: −181.56[1] mas/yr
Parallax (π) 11.10 ± 0.18[1] mas
Distance 294 ± 5 ly
(90 ± 1 pc)
Absolute magnitude (MV) −0.87[5]
Details
Mass 1.6[6] M
Radius 54[4] R
Luminosity 631[4] L
Surface gravity (log g) 1.0[4] cgs
Temperature 4,009[4] K
Metallicity [Fe/H] 0.06[4] dex
Rotational velocity (v sin i) 3.8[4] km/s
Other designations
3 Virginis, ν Vir, BD+07° 2479, FK5 1302, HD 102212, HIP 57380, HR 4517, SAO 119035.[7]
Database references
SIMBAD data

Nu Virginis (ν Vir, ν Virginis) is a star in the zodiac constellation of Virgo. It has an apparent visual magnitude of 4.04[2] and can be seen with the naked eye. Because the star lies near the ecliptic it is subject to occultations by the Moon.[8] Parallax measurements provide an estimated distance of around 294 light years from the Sun.

Nu Virginis is an M-type red giant with a stellar classification of M1 III.[3] It is an SRB-type[9] semiregular variable star with its brightness varying by 0.0125 in magnitude.[10] These variations have four periods lasting 11.1, 12.3, 16.8, and 23.7 days.[11] This star has about 1.6 times the mass of the sun, but it has expanded to 54 times the Sun's radius and shines 631 times as brightly as the Sun. The effective temperature of its outer atmosphere is 4,009 K.[6]

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, Bibcode:2007A&A...474..653V, arXiv:0708.1752Freely accessible, doi:10.1051/0004-6361:20078357. 
  2. ^ a b c d Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV data, SIMBAD, Bibcode:1986EgUBV........0M. 
  3. ^ a b Morgan, W. W.; Keenan, P. C. (1973), "Spectral Classification", Annual Review of Astronomy and Astrophysics, 11: 29–50, Bibcode:1973ARA&A..11...29M, doi:10.1146/annurev.aa.11.090173.000333. 
  4. ^ a b c d e f g 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. ^ Pace, G.; et al. (April 2003), "The Wilson-Bappu effect: A tool to determine stellar distances", Astronomy and Astrophysics, 401: 997–1007, Bibcode:2003A&A...401..997P, arXiv:astro-ph/0301637Freely accessible, doi:10.1051/0004-6361:20030163. 
  6. ^ a b Tsuji, Takashi (May 2007). "Isotopic abundances of Carbon and Oxygen in Oxygen-rich giant stars". In Kupka, F.; Roxburgh, I.; Chan, K. Convection in Astrophysics, Proceedings of IAU Symposium #239 held 21-25 August, 2006 in Prague, Czech Republic. Proceedings of the International Astronomical Union. 2. pp. 307–310. Bibcode:2007IAUS..239..307T. arXiv:astro-ph/0610180Freely accessible. doi:10.1017/S1743921307000622. 
  7. ^ "mu. nu. Vir -- Semi-regular pulsating Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2016-09-08. 
  8. ^ White, Nathaniel M.; Feierman, Barry H. (September 1987), "A Catalog of Stellar Angular Diameters Measured by Lunar Occultation", Astronomical Journal, 94: 751, Bibcode:1987AJ.....94..751W, doi:10.1086/114513. 
  9. ^ Kazarovets, E. V.; et al. (1999), "The 74th Special Name-list of Variable Stars", Information Bulletin on Variable Stars (4659), Bibcode:1999IBVS.4659....1K. 
  10. ^ Koen, Chris; Eyer, Laurent (March 2002). "New periodic variables from the Hipparcos epoch photometry". Monthly Notices of the Royal Astronomical Society. 331 (1): 45–59. Bibcode:2002MNRAS.331...45K. arXiv:astro-ph/0112194Freely accessible. doi:10.1046/j.1365-8711.2002.05150.x. 
  11. ^ Tabur, V.; et al. (December 2009), "Long-term photometry and periods for 261 nearby pulsating M giants", Monthly Notices of the Royal Astronomical Society, 400 (4): 1945–1961, Bibcode:2009MNRAS.400.1945T, arXiv:0908.3228Freely accessible, doi:10.1111/j.1365-2966.2009.15588.x.