Rho Virginis

ρ Virginis
	Location of ρ Virginis (circled)
Observation data; Epoch J2000.0 Equinox J2000.0
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
	30 Virginis, BD+11°2485, FK5 1326, HD 110411, HIP 61960, HR 4828, SAO 100211
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

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.
Wielen, R.; et al. (1999), Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions, Astronomisches Rechen-Institut Heidelberg, Bibcode:1999VeARI..35....1W.
Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (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, arXiv:astro-ph/0207488, Bibcode:2002MNRAS.336.1030P, doi:10.1046/j.1365-8711.2002.05865.x.
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, arXiv:0812.2198, Bibcode:2009ApJ...694..165M, doi:10.1088/0004-637X/694/1/165.
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, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224.
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, arXiv:astro-ph/0311546, Bibcode:2004ApJ...603..738Z, doi:10.1086/381700.

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.

[aaa474_2_653-1] 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.

[scfs-2] Wielen, R.; et al. (1999), Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions, Astronomisches Rechen-Institut Heidelberg, Bibcode:1999VeARI..35....1W.

[aj74_375-3] Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.

[clpl4_99-4] Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99), Bibcode:1966CoLPL...4...99J.

[Paunzen2002-5] 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, arXiv:astro-ph/0207488, Bibcode:2002MNRAS.336.1030P, doi:10.1046/j.1365-8711.2002.05865.x.

[apj694_1_165-6] 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, arXiv:0812.2198, Bibcode:2009ApJ...694..165M, doi:10.1088/0004-637X/694/1/165.

[aaa277_1_139-7] Sturenburg, S. (September 1993), "Abundance Analysis of Lambda-Bootis Stars", Astronomy and Astrophysics, 277 (1): 139, Bibcode:1993A&A...277..139S.

[aaa463_2_671-8] 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, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224.

[apj603_2_738-9] 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, arXiv:astro-ph/0311546, Bibcode:2004ApJ...603..738Z, doi:10.1086/381700.