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Sigma Virginis

σ Virginis
Location of σ Virginis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Virgo
Right ascension 13h 17m 36.28327s[1]
Declination +05° 28′ 11.5221″[1]
Apparent magnitude (V) 4.86[2]
Characteristics
Spectral type M1 III[3]
U−B color index +1.86[2]
B−V color index +1.62[2]
Variable type suspected[4]
Astrometry
Radial velocity (Rv)−28.26±0.30[5] km/s
Proper motion (μ) RA: −6.06[1] mas/yr
Dec.: +9.14[1] mas/yr
Parallax (π)4.83 ± 0.19 mas[1]
Distance680 ± 30 ly
(207 ± 8 pc)
Absolute magnitude (MV)−1.80[6]
Details
Radius98[7] R☉
Luminosity1,610[7] L☉
Surface gravity (log g)0.42[7] cgs
Temperature3,690[7] K
Other designations
σ Vir, 60 Virginis, BD+06°2722, FK5 1344, HD 115521, HIP 64852, HR 5015, SAO 119855[8]
Database references
SIMBADdata

Sigma Virginis (σ Vir, σ Virginis) is a star in the zodiac constellation of Virgo. It can be faintly seen with the naked eye with a baseline apparent visual magnitude of 4.86.[2] Based upon parallax measurements, the distance to this star is roughly 680 light-years.

A light curve for Sigma Virginis, plotted from Hipparcos data[9]

This is an evolved red giant star with a stellar classification of M1 III.[3] It is a suspected variable star with a brightness that ranges from magnitude +4.77 to +4.86.[4] This variation has pulsation periods of 23.4, 24.3, 27.9 and 34.1 days.[3] The effective temperature of the stellar atmosphere is around 3,800 K, and it shines with 1,734 times the luminosity of the Sun.[7]

References

  1. ^ a b c d e 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 ^ a b c d Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M.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 c Tabur, V.; Bedding, T. R. (2009), "Long-term photometry and periods for 261 nearby pulsating M giants", Monthly Notices of the Royal Astronomical Society, 400 (4): 1945–61, arXiv:0908.3228, Bibcode:2009MNRAS.400.1945T, doi:10.1111/j.1365-2966.2009.15588.x, S2CID 15358380.
  4. ^ a b Kukarkin, B. V.; et al. (1981), "Nachrichtenblatt der Vereinigung der Sternfreunde e.V. (Catalogue of suspected variable stars)", Nachrichtenblatt der Vereinigung der Sternfreunde, Moscow: Academy of Sciences USSR Shternberg, Bibcode:1981NVS...C......0K.
  5. ^ Famaey, B.; et al. (2005), "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters", Astronomy and Astrophysics, 430: 165–186, arXiv:astro-ph/0409579, Bibcode:2005A&A...430..165F, doi:10.1051/0004-6361:20041272, S2CID 17804304.
  6. ^ 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.
  7. ^ a b c d e McDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017), "Fundamental parameters and infrared excesses of Tycho-Gaia stars", Monthly Notices of the Royal Astronomical Society, 471 (1): 770, arXiv:1706.02208, Bibcode:2017MNRAS.471..770M, doi:10.1093/mnras/stx1433, S2CID 73594365.
  8. ^ "sig Vir", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2016-09-16.
  9. ^ "/ftp/cats/more/HIP/cdroms/cats", Centre de Données astronomiques de Strasbourg, Strasbourg astronomical Data Center, retrieved 15 October 2022.
Quelle: https://en.wikipedia.org/wiki/Sigma_Virginis