Astronomy:Rho Virginis
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| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Virgo |
| Right ascension | 12h 41m 53.05658s[1] |
| Declination | +10° 14′ 51.1699″[1] |
| Apparent magnitude (V) | +4.88[2] |
| Characteristics | |
| Spectral type | A0 V[3] |
| U−B color index | +0.03[4] |
| B−V color index | +0.09[4] |
| Astrometry | |
| Radial velocity (Rv) | +1.6[2] km/s |
| Proper motion (μ) | RA: +82.67[1] mas/yr Dec.: –89.08[1] mas/yr |
| Parallax (π) | 27.57 ± 0.21[1] mas |
| Distance | 118.3 ± 0.9 ly (36.3 ± 0.3 pc) |
| Absolute magnitude (MV) | +1.90±0.28[5] |
| Details | |
| Mass | 2.0[6] M☉ |
| Radius | 1.6[6] R☉ |
| Luminosity | 14[6] L☉ |
| Surface gravity (log g) | 4.36[7] cgs |
| Temperature | 8,930[6] K |
| Metallicity [Fe/H] | –1.00[7] dex |
| Rotational velocity (v sin i) | 154[8] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
Rho Virginis (ρ Vir, ρ Virginis) is the Bayer designation for a star in the constellation Virgo. It has an apparent visual magnitude of +4.9,[2] making it a challenge to view with the naked eye from an urban area (according to the Bortle Dark-Sky Scale). The distance to this star has been measured directly using the parallax method, which places it 118.3 light-years (36.3 parsecs) away with a margin of error of about a light year.[1]
Rho Virginis is an A-type main sequence star with a stellar classification of A0 V.[3] It is larger than the Sun with a radius 60%[6] larger and about twice the mass. As such it is generating energy at a higher rate than the Sun, with a luminosity 14[6] times greater. The outer atmosphere has an effective temperature of 8,930 K,[6] which is what gives it the white-hued glow of an A-type star. It is classified as a Delta Scuti type variable star and its brightness varies by 0.02 magnitudes over periods of 0.5 to 2.4 hours.
This star has been established as a Lambda Boötis star that displays low abundances of iron peak elements. It displays an excess of infrared emission, but it is unclear whether this is being caused by a circumstellar debris disk or from the star passing through and heating up a diffuse interstellar dust cloud. Most likely it is the former,[6] in which case the dusty disk has a radius of around 37 AU and a mean temperature of 90 K.[9]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode: 2007A&A...474..653V.
- ↑ 2.0 2.1 2.2 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.
- ↑ 3.0 3.1 Cowley, A. et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal 74: 375–406, doi:10.1086/110819, Bibcode: 1969AJ.....74..375C.
- ↑ 4.0 4.1 Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99): 99, Bibcode: 1966CoLPL...4...99J.
- ↑ Paunzen, E. et al. (November 2002), "The status of Galactic field λ Bootis stars in the post-Hipparcos era", Monthly Notices of the Royal Astronomical Society 336 (3): 1030–1042, doi:10.1046/j.1365-8711.2002.05865.x, Bibcode: 2002MNRAS.336.1030P.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 Martínez-Galarza, J. R. et al. (March 2009), "Infrared Emission by Dust Around λ Bootis Stars: Debris Disks or Thermally Emitting Nebulae?", The Astrophysical Journal 694 (1): 165–173, doi:10.1088/0004-637X/694/1/165, Bibcode: 2009ApJ...694..165M.
- ↑ 7.0 7.1 Sturenburg, S. (September 1993), "Abundance Analysis of Lambda-Bootis Stars", Astronomy and Astrophysics 277 (1): 139, Bibcode: 1993A&A...277..139S.
- ↑ Royer, F.; Zorec, J.; Gómez, A. E. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics 463 (2): 671–682, doi:10.1051/0004-6361:20065224, Bibcode: 2007A&A...463..671R.
- ↑ Zuckerman, B.; Song, Inseok (March 2004), "Dusty Debris Disks as Signposts of Planets: Implications for Spitzer Space Telescope", The Astrophysical Journal 603 (2): 738–743, doi:10.1086/381700, Bibcode: 2004ApJ...603..738Z.
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