Tau Virginis
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Virgo |
| Right ascension | 14h 01m 38.79341s[1] |
| Declination | +01° 32′ 40.3145″[1] |
| Apparent magnitude (V) | 4.2777±0.0007[2] |
| Characteristics | |
| Spectral type | A2IV/V[3] |
| U−B color index | +0.12[4] |
| B−V color index | +0.11[4] |
| Astrometry | |
| Radial velocity (Rv) | −6.7±0.9[5] km/s |
| Proper motion (μ) | RA: +17.49[1] mas/yr Dec.: −21.27[1] mas/yr |
| Parallax (π) | 14.50 ± 0.18 mas[1] |
| Distance | 225 ± 3 ly (69.0 ± 0.9 pc) |
| Absolute magnitude (MV) | +0.5[6] |
| Details | |
| Mass | 1.96[7] M☉ |
| Radius | 1.6[8] R☉ |
| Luminosity | 70[9] L☉ |
| Surface gravity (log g) | 3.39[7] cgs |
| Temperature | 8,413±286[7] K |
| Metallicity [Fe/H] | −0.19[10] dex |
| Rotational velocity (v sin i) | 186[11] km/s |
| Age | 724[7] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Tau Virginis (τ Vir, τ Virginis) is a single[13] star in the zodiac constellation Virgo. With an apparent visual magnitude of 4.28,[2] it is faintly visible to the naked eye. The distance to Tau Virginis, based upon parallax measurements, is approximately 225 light years with a margin of error of ±3 light years.
This star has a stellar classification of A2IV/V,[3] which matches the spectrum of an A-type main sequence star mixed with spectral traits of a subgiant. It is about 700[7] million years old and is spinning rapidly with a projected rotational velocity of 186 km/s.[11] The star has nearly double[7] the mass of the Sun and about 160% of the Sun's radius.[8] It shines with 70[9] times the luminosity of the Sun and has an effective temperature of 8413 K in its outer atmosphere.[7]
Tau Virginis has multiple visual companions, listed below:[14]
| Companion | Visual Magnitude |
Angular Separation |
Position Angle |
Year Measured |
|---|---|---|---|---|
| B | 9.41 | 82.70″ | 287° | 2012 |
| C | 13.10 | 176.70″ | 353° | 2000 |
| D | 9.68 | 342.70″ | 85° | 2012 |
| E | 12.00 | 14.6″ | 175° | 2009 |
References
[edit]- ^ 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.
- ^ a b Adelman, S. J. (February 2001). "Research Note Hipparcos photometry: The least variable stars". Astronomy and Astrophysics. 367 (1): 297–298. Bibcode:2001A&A...367..297A. doi:10.1051/0004-6361:20000567.
- ^ a b Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars, Vol. 5", Michigan Spectral Survey, 05, Bibcode:1999MSS...C05....0H
- ^ a b Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M
- ^ Gontcharov, G. A. (2006), "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065, S2CID 119231169.
- ^ Blondel, P. F. C.; Djie, H. R. E. Tjin A. (September 2006), "Modeling of PMS Ae/Fe stars using UV spectra" (PDF), Astronomy and Astrophysics, 456 (3): 1045–1068, Bibcode:2006A&A...456.1045B, doi:10.1051/0004-6361:20040269.
- ^ a b c d e f g David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
- ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics", Astronomy and Astrophysics, 367 (2): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
- ^ a b McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
- ^ Morossi, C.; et al. (September 2002), "Metallicity Determinations from Ultraviolet-Visual Spectrophotometry. I. The Test Sample", The Astrophysical Journal, 577 (1): 377–388, Bibcode:2002ApJ...577..377M, doi:10.1086/342144.
- ^ a b Royer, F.; et al. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224, S2CID 18475298.
- ^ "* tau Vir". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-09-16.
- ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920, retrieved 2015-07-22.
