32 Virginis, also known as FM Virginis, is a star located about 250 light years from the Earth, in the constellation Virgo.[2] Its apparent magnitude ranges from 5.20 to 5.28, making it faintly visible to the naked eye of an observer well away from city lights.[3] 32 Virginis is a binary star,[11] and the more massive component of the binary is a Delta Scuti variable star which oscillates with a dominant period of 103.51 minutes.[11]
 A light curve for FM Virginis, plotted from TESS data.[1] The 103.51 minute period is marked in red. | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Virgo |
| Right ascension | 12h 45m 37.05805s[2] |
| Declination | +07° 40′ 23.9689″[2] |
| Apparent magnitude (V) | 5.20 - 5.28[3] |
| Characteristics | |
| Spectral type | F0 IIIm (primary)[4] + A7V (secondary)[5] |
| U−B color index | +0.15 [6] |
| B−V color index | +0.33[6] |
| Variable type | Delta Scuti[3] |
| Astrometry | |
| Proper motion (μ) | RA: −107.527±0.697[2] mas/yr Dec.: 4.915±0.344[2] mas/yr |
| Parallax (π) | 12.8075 ± 0.3062 mas[2] |
| Distance | 255 ± 6 ly (78 ± 2 pc) |
| Absolute magnitude (MV) | +1.75[5] |
| Orbit[7] | |
| Period (P) | 38.324 d |
| Eccentricity (e) | 0.074±0.006 |
| Periastron epoch (T) | 2434039.463±0.038 |
| Argument of periastron (ω) (primary) | 210.02±5.1° |
| Semi-amplitude (K1) (primary) | 48.05±0.33 km/s |
| Details | |
| primary (Delta Scuti variable) | |
| Mass | 2.05[5] M☉ |
| Surface gravity (log g) | 3.75[8] cgs |
| Temperature | 7,450[8] K |
| Rotational velocity (v sin i) | 24[8] km/s |
| secondary | |
| Mass | 1.9[5] M☉ |
| Rotational velocity (v sin i) | 140[8] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
In 1914, Walter Sydney Adams announced that 32 Virginis is a spectroscopic binary.[12] John Beattie Cannon published the first set of orbital elements for the binary system in 1915.[13] Corrado Bartolini et al. made photometric observations of the star in early 1971, and found that the star showed variability due to pulsations.[14] In 1974, 32 Virginis was given the variable star designation FM Virginis.[15] Donald Kurtz et al. determined that the star was a Delta Scuti variable, in 1976.[8]
The primary star is believed to be an Am star similar to rho Puppis - a pulsating post-main sequence star.[16]
References
edit- ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 14 January 2023.
- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c 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.
- ^ Pyper, Diane M.; Adelman, Saul J. (August 2021). "Light Curve Changes and Possible Precession in mCP Stars". Publications of the Astronomical Society of the Pacific. 133 (1026): 084203. Bibcode:2021PASP..133h4203P. doi:10.1088/1538-3873/ac1ac0. S2CID 237301384.
- ^ a b c d Mitton, J.; Stickland, D. J. (January 1979). "The nature of the components of the spectroscopic binary, 32 Virginis". Monthly Notices of the Royal Astronomical Society. 186 (2): 189–195. Bibcode:1979MNRAS.186..189M. doi:10.1093/mnras/186.2.189. Retrieved 16 January 2023.
- ^ a b Renson, P.; Manfroid, J. (May 2009). "Catalogue of Ap, HgMn and Am stars" (PDF). Astronomy and Astrophysics. 498 (3): 961–966. Bibcode:2009A&A...498..961R. doi:10.1051/0004-6361/200810788. Retrieved 16 January 2023.
- ^ Bertiau, F. C. (May 1957). "The Orbits of the Spectroscopic Binaries Rho Orionis, Eta Bootis, and 32 Virginis". Astrophysical Journal. 125: 696. Bibcode:1957ApJ...125..696B. doi:10.1086/146343. Retrieved 16 January 2023.
- ^ a b c d e Kurtz, D. W.; Breger, M.; Evans, S. W.; Sandmann, W. H. (July 1976). "Metallicism, pulsation, and the nature of 32 Virginis". Astrophysical Journal. 207: 181–189. Bibcode:1976ApJ...207..181K. doi:10.1086/154482.
- ^ "d02 Vir -- delta Sct Variable". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2023-01-15.
- ^ Douglas, A. V. (November 1926). "Spectroscopic magnitudes of A-type stars". Astrophysical Journal. 64: 262–270. Bibcode:1926ApJ....64..262D. doi:10.1086/143011. Retrieved 16 January 2023.
- ^ a b Liakos, Alexios; Niarchos, Panagiotis (February 2017). "Catalogue and properties of δ Scuti stars in binaries". Monthly Notices of the Royal Astronomical Society. 465 (1): 1181–1200. arXiv:1611.00200. Bibcode:2017MNRAS.465.1181L. doi:10.1093/mnras/stw2756.
- ^ Adams, W. S. (December 1914). "Ten Spectroscopic Binaries". Publications of the Astronomical Society of the Pacific. 26 (156): 261. Bibcode:1914PASP...26..261A. doi:10.1086/122362. S2CID 122672368.
- ^ Cannon, J. B. (1915). "Orbit of Boss 3323". Publications of the Dominion Observatory Ottawa. 2: 367–384. Bibcode:1915PDO.....2..367C. Retrieved 16 January 2023.
- ^ Bartolini, C.; Grilli, F.; Parmeggiani, G. (August 1972). "32 Virginis: a pulsating Am star". Information Bulletin on Variable Stars. 704 (1): 1. Bibcode:1972IBVS..704....1B. Retrieved 16 January 2023.
- ^ Kukarkin, B. V.; Kholopov, P. N.; Kukarkina, N. P.; Perova, N. B. (January 1975). "60th Name-List of Variable Stars". Information Bulletin on Variable Stars. 961 (1): 1. Bibcode:1975IBVS..961....1K. Retrieved 16 January 2023.
- ^ Aurière, M.; Wade, G. A.; Lignières, F.; Hui-Bon-Hoa, A.; Landstreet, J. D.; Iliev, I. Kh.; Donati, J. F.; Petit, P.; Roudier, T.; Théado, S. (November 2010). "No detection of large-scale magnetic fields at the surfaces of Am and HgMn stars" (PDF). Astronomy and Astrophysics. 523: A40. arXiv:1008.3086. Bibcode:2010A&A...523A..40A. doi:10.1051/0004-6361/201014848. S2CID 118643022. Retrieved 16 January 2023.