Psi Virginis

Psi Virginis (ψ Vir, ψ Virginis) is a suspected^[5] binary star^[3] system in the zodiac constellation of Virgo. It can be seen with the naked eye and has an apparent visual magnitude of about 4.8. Based upon the annual parallax shift of 5.99 milliarcseconds, the distance to this star is roughly 540 light years. The angular size of Psi Virginis was measured on December 26, 1975 during an occultation by the Moon, yielding the estimate 6.5±0.3 mas.^[11]

A visual band light curve for Psi Virginis, plotted from data published by Tabur et al. (2009)^[12]

ψ Virginis

Location of ψ Virginis (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Virgo
Right ascension	12h 54m 21.16342s[1]
Declination	−09° 32′ 20.3783″[1]
Apparent magnitude (V)	4.73 - 4.96[2]
Characteristics
Spectral type	M3 IIICa-1[3]
U−B color index	+1.57[4]
B−V color index	+1.58[4]
Variable type	LB[2]
Astrometry
Radial velocity (Rv)	+12.82[5] km/s
Proper motion (μ)	RA: −18.08[1] mas/yr Dec.: −19.52[1] mas/yr
Parallax (π)	5.99 ± 0.23 mas[1]
Distance	540 ± 20 ly (167 ± 6 pc)
Absolute magnitude (MV)	−1.34[6]
Details
Mass	3.95[7] M☉
Radius	93[8] R☉
Luminosity	3,548[7] L☉
Surface gravity (log g)	1.05[9] cgs
Temperature	3,500[7] K
Metallicity [Fe/H]	−0.10[9] dex
Other designations
ψ Vir, 40 Virginis, BD−08°3449, FK5 1335, HD 112142, HIP 62985, HR 4902, SAO 139033[10]
Database references
SIMBAD	data

The primary component is an evolved red giant star with a stellar classification of M3 IIICa-1.^[3] It is an irregular variable^[13] with seven measured pulsation periods ranging from 22.4 to 162.6 days, and amplitudes ranging up to 0.^m022.^[12] The star is a bright X-ray source with a luminosity of 21.58×10²⁹ ergs s⁻¹.^[14] There is a magnitude 8.3 companion at an angular separation of 0.04 arcseconds.^[3]

References

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, S2CID 18759600.
2. Samus', N. N.; Kazarovets, E. V.; Durlevich, O. V.; Kireeva, N. N.; Pastukhova, E. N. (2017), "General catalogue of variable stars: Version GCVS 5.1", Astronomy Reports, 61 (1): 80, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
3. 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.
4. Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M
5. Famaey, B.; et al. (2009), "Spectroscopic binaries among Hipparcos M giants. I. Data, orbits, and intrinsic variations", Astronomy and Astrophysics, 498 (2): 627–640, arXiv:0901.0934, Bibcode:2009A&A...498..627F, doi:10.1051/0004-6361/200810698, S2CID 18739721.
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. Charbonnel, C.; Lagarde, N.; Jasniewicz, G.; North, P. L.; Shetrone, M.; Krugler Hollek, J.; Smith, V. V.; Smiljanic, R.; Palacios, A.; Ottoni, G. (2020), "Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era", Astronomy and Astrophysics, 633: A34, arXiv:1910.12732, Bibcode:2020A&A...633A..34C, doi:10.1051/0004-6361/201936360, S2CID 204907220.
8. Stassun K.G.; et al. (October 2019), "The revised TESS Input Catalog and Candidate Target List", The Astronomical Journal, 158 (4): 138, arXiv:1905.10694, Bibcode:2019AJ....158..138S, doi:10.3847/1538-3881/ab3467, S2CID 166227927.
9. Wu, Yue; Singh, H. P; Prugniel, P; Gupta, R; Koleva, M (2010), "Coudé-feed stellar spectral library – atmospheric parameters", Astronomy & Astrophysics, 525: A71, arXiv:1009.1491, Bibcode:2011A&A...525A..71W, doi:10.1051/0004-6361/201015014, S2CID 53480665.
10. "psi Vir -- Long-period variable star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2016-09-19.
11. Evans, D. S.; et al. (October 1977), "Angular diameter of psi Vir (SAO 139033) and chi 1Ori (SAO 077705)", Astronomical Journal, 82: 828–831, Bibcode:1977AJ.....82..828E, doi:10.1086/112134.
12. 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.
13. Mennessier, M. O.; et al. (August 2001), "Long period variable stars: galactic populations and infrared luminosity calibrations", Astronomy and Astrophysics, 374 (3): 968–979, arXiv:astro-ph/0105552, Bibcode:2001A&A...374..968M, doi:10.1051/0004-6361:20010764, S2CID 15721872.
14. Makarov, Valeri V. (October 2003), "The 100 Brightest X-Ray Stars within 50 Parsecs of the Sun", The Astronomical Journal, 126 (4): 1996–2008, Bibcode:2003AJ....126.1996M, doi:10.1086/378164.