FG Virginis

	FG Virginis
Observationsdata; Epok: J2000.0
Stjärnbild	Jungfrun
Rektascension	12t 14m 15,457s
Deklination	-05° 42′ 59,75″
Skenbar magnitud (V)	+6,56 (6,53 - 6,58)
Stjärntyp
Spektraltyp	A8/9 V
U–B	+0,05
B–V	+0,277 ± 0,007
Variabeltyp	Delta Scuti-variabel
Astrometri
Radialhastighet (Rv)	+16,4 ± 0,6 km/s
Egenrörelse (µ)	RA: -85,128 mas/år; Dek.: +114,628 mas/år
Parallax (π)	11,9261 ± 0,0308
Avstånd	273,5 ± 0,7 lå (83,8 ± 0,2 pc)
Absolut magnitud (MV)	+2,10
Detaljer
Massa	1,80 M☉
Radie	2,27 R☉
Luminositet	11,95 L☉
Temperatur	7 425 K
Vinkelhastighet	21,3 ± 1,0 km/s
Andra beteckningar
	HD 106384, BD-04 3235, CCDM J12143-0543A, GSC 04946-01300, HIC 59676, HIP 59676, 2MASS J12141545-0542597, PLX 2817, PPM 195288, SAO 138664, TD1 16150, TYC 4946-1300-1, FG Virginis, WDS J12143-0543A, Gaia DR2 3596384135093726848, Gaia DR3 3596384135093726848, Gaia DR1 3596384130796880512

FG Virginis är en välstuderad variabel stjärna i stjärnbilden Jungfrun. Den är en svag stjärna, nära den nedre gränsen för att kunna ses för blotta ögat, med en skenbar magnitud som varierar från 6,53 ner till 6,58. Stjärnan är belägen på ett avstånd av 273,5 ljusår från solen baserat på parallaxmätningar, och rör bort från solsystemet med en radialhastighet på +16 km/s. På grund av dess position nära ekliptikan är den utsatt för ockultationer med månen.

Observation

Stjärnans variation rapporterades först av O.J. Eggen 1971, som klassificerade den som en ultrakortperiodisk cepheid – en föreslagen kategori av pulserande stjärnor i instabilitetsremsan. Den grupperades därefter i klassen Delta Scuti-variabler, vilka visar en pulseringsperiod på mindre än ett dygn. Observationer 1984 av P. Lopez de Coca visade minst en pulseringssperiod med en cykel på 1,9 timmar. L. Mantegazza et al. kunde 1994 notera sju eller fler pulseringslägen, där det tidigare observerade dominanta läget var en radiell pulsering med en frekvens på 12,72 cykler per dygn.

Stjärnan blev intressant för asteroseismologistudier på grund av dess relativt långsamma rotationshastighet och de många pulseringslägena. En kampanj på flera platser med Whole Earth Telescope-nätverket genomfördes 1993 för att observera stjärnan, som noterade tio lägen. Detta ökade till 24 frekvenser 1998, sedan 67 oberoende frekvenser med totalt 79 år 2005. Bevis tyder på att det finns många fler sådana lägen.

Egenskaper

FG Virginis är en huvudseriestjärna av spektraltyp A med spektralklass A8/9V, men den är nära slutet av sin tid i huvudserien. Den klassificeras som en Delta Scuti-variabel vars ljusstyrka varierar med en amplitud på 0,040 i skenbar magnitud och en period på 1,89 timmar. Elementförekomsten liknar solens, även om det finns ett litet överskott av barium och underskott av svavel och kol. Den har en beräknad rotationshastighet på 21 km/s, men den faktiska rotationshastigheten är sannolikt mycket högre, ca 80 km/s.

Referenser

Den här artikeln är helt eller delvis baserad på material från engelskspråkiga Wikipedia, FG Virginis, 17 december 2025.

Noter

1 2 3 4 5 6 Brown, A. G. A.; et al. (Gaia collaboration) (2021), "Gaia Early Data Release 3: Summary of the contents and survey properties", Astronomy & Astrophysics, 649: A1, arXiv:2012.01533, Bibcode:2021A&A...649A...1G, doi:10.1051/0004-6361/202039657, S2CID 227254300 (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
1 2 3 4 on", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
1 2 3 Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
1 2 Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Bibcode:1999MSS...C05....0H.
1 2 Rodríguez, E.; et al. (June 2000), "A revised catalogue of delta Sct stars", Astronomy & Astrophysics Supplement Series, 144 (3): 469–474, Bibcode:2000A&AS..144..469R, doi:10.1051/aas:2000221, hdl:10261/226673.
1 2 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.
↑ Breger, M.; Pamyatnykh, A. A. (May 2006), "Amplitude variability or close frequencies in pulsating stars - the δ Scuti star FG Vir", Monthly Notices of the Royal Astronomical Society, 368 (2): 571–578, arXiv:astro-ph/0602037, Bibcode:2006MNRAS.368..571B, doi:10.1111/j.1365-2966.2006.10119.x, S2CID 18429588.
↑ Zima, W.; et al. (June 2004), "Moment Method and Pixel-by-Pixel Method: Complementary Mode Identification I. Testing FG Vir-like pulsation modes", Communications in Asteroseismology, 144: 5–22, Bibcode:2004CoAst.144....5Z, doi:10.1553/cia144s5.
↑ Zima, W.; et al. (August 2006), "A new method for the spectroscopic identification of stellar non-radial pulsation modes. II. Mode identification of the δ Scuti star FG Virginis", Astronomy & Astrophysics, 455 (1): 235–246, arXiv:astro-ph/0606515, Bibcode:2006A&A...455..235Z, doi:10.1051/0004-6361:20064877, S2CID 54036626.
1 2 3 Breger, M.; Lenz, P. (February 2019), "Photometric data by the Delta Scuti Network. II. EE Cam, FG Vir, 44 Tau", The Journal of Astronomical Data, 25 (1): 6, Bibcode:2019JAD....25....1B.
↑ https://simbad.cds.unistra.fr/simbad/sim-id?Ident=FG+Vir Arkiverad 15 januari 2026 hämtat från the Wayback Machine.. Hämtad 2025-12-25.
↑ "FG Vir", SIMBAD, Centre de données astronomiques de Strasbourg, hämtad 2022-06-14.
↑ Eitter, J. J.; Beavers, W. I. (June 1979), "Lunar occultation summary. III", Astrophysical Journal Supplement Series, 40: 475–486, Bibcode:1979ApJS...40..475E, doi:10.1086/190595. See event no. 528.
1 2 Breger, M.; et al. (May 1995), "The δ Scuti star FG Virginis. I. Multiple pulsation frequencies determined with a combined DSN/WET campaign", Astronomy & Astrophysics, 297: 473, Bibcode:1995A&A...297..473B.
↑ Eggen, O. J. (December 1971), "The Nature of the Blue Stragglers in the Old Disk Population", Publications of the Astronomical Society of the Pacific, 83 (496): 762, Bibcode:1971PASP...83..762E, doi:10.1086/129212, S2CID 120025134.
↑ Baglin, A.; et al. (March 1973), "Delta Scuti stars", Astronomy & Astrophysics, 23: 221, Bibcode:1973A&A....23..221B.
↑ Lopez de Coca, P.; et al. (January 1984), "Narrow Band Photometry of FG Vir", Information Bulletin on Variable Stars, 2465: 1, Bibcode:1984IBVS.2465....1L.
↑ Mantegazza, L.; et al. (July 1994), "Simultaneous intensive photometry and high resolution spectroscopy of δ Scuti stars I. Mode typing of HD 106384 = FG Virginis", Astronomy & Astrophysics, 287: 95–104, Bibcode:1994A&A...287...95M.
↑ Breger, M.; et al. (January 1999), "The delta Scuti star FG Virginis. IV. Mode identifications and pulsation modelling", Astronomy & Astrophysics, 341: 151–162, arXiv:astro-ph/9811338, Bibcode:1999A&A...341..151B.
↑ Breger, M.; et al. (June 2005), "Detection of 75+ pulsation frequencies in the δ Scuti star FG Virginis", Astronomy & Astrophysics, 435 (3): 955–965, arXiv:astro-ph/0502073, Bibcode:2005A&A...435..955B, doi:10.1051/0004-6361:20042480, S2CID 119042031.
↑ Mittermayer, P.; Weiss, W. W. (September 2003), "Atmospheric properties and abundances of the delta Scuti star FG Virginis", Astronomy & Astrophysics, 407 (3): 1097–1101, Bibcode:2003A&A...407.1097M, doi:10.1051/0004-6361:20030930, S2CID 123022971.

Vidare läsning

Haas, P. (2011), ”Analyses of Crawford's uvby β calibrations using the pulsational variations of FG Vir”, Communications in Asteroseismology 162: 3, doi:10.1553/cia162s3, Bibcode: 2011CoAst.162....3H.
Lenz, P.; Daszyńska-Daszkiewicz, J.; Pamyatnykh, A. A.; Breger, M. (April 2008), ”Determination of intrinsic mode amplitudes of the δ Scuti stars FG Vir and 44 Tau”, Communications in Asteroseismology 153: 40–48, doi:10.1553/cia_153s40, Bibcode: 2008CoAst.153...40L.
Daszyńska-Daszkiewicz, J.; Dziembowski, W. A.; Pamyatnykh, A. A.; Breger, M.; Zima, W.; Houdek, G. (August 2005), ”Inferences from pulsational amplitudes and phases for multimode δ Sct star FG Vir”, Astronomy & Astrophysics 438 (2): 653–660, doi:10.1051/0004-6361:20052902, Bibcode: 2005A&A...438..653D.
Kirbiyik, H.; Civelek, R.; Kiziloğlu, N. (February 2005), ”A new oscillating model suggestion for FG Vir”, Astrophysics and Space Science 295 (4 7): 473–484, doi:10.1007/s10509-005-1085-y, Bibcode: 2005Ap&SS.295..473K.
Breger, M.; Rodler, F.; Pretorius, M. L.; Martín-Ruiz, S.; Amado, P. J.; Costa, V.; Garrido, R.; López de Coca, P.; et al. (May 2004), ”The δ Scuti star FG Vir. V. The 2002 photometric multisite campaign”, Astronomy & Astrophysics 419 (2): 695–701, doi:10.1051/0004-6361:20035830, Bibcode: 2004A&A...419..695B.
Mantegazza, L.; Poretti, E. (December 2002), ”Line profile variations in the delta Scuti star FG Virginis: A high number of axisymmetric modes”, Astronomy & Astrophysics 396 (3): 911–916, doi:10.1051/0004-6361:20021456, Bibcode: 2002A&A...396..911M.
Templeton, Matthew; Basu, Sarbani; Demarque, Pierre (December 2001), ”Asteroseismology of δ Scuti Stars: A Parameter Study and Application to Seismology of FG Virginis”, The Astrophysical Journal 563 (2): 999–1012, doi:10.1086/324041, Bibcode: 2001ApJ...563..999T.
Zima, W. (July 2001), ”The Spectroscopic and Photometric DSN Campaign 2002 of FG Vir”, Communications in Asteroseismology 140: 57–58, Bibcode: 2001CoAst.140...57Z.
Dziembowski, W. A.; Balona, L. A.; Goupil, M. -J.; Pamyatnykh, A. A. (November 1998), Kjeldsen, H.; Bedding, T. R., red., ”Oscillations in XX Pyx and FG VIR and the prospects for asteroseismology of delta Scuti stars from space”, The First MONS Workshop: Science with a Small Space Telescope, held in Aarhus, Denmark, June 29–30, 1998 (Aarhus Universitet): s. 127, Bibcode: 1998mons.proc..127D.
Viskum, M.; Kjeldsen, H.; Bedding, T. R.; dall, T. H.; Baldry, I. K.; Bruntt, H.; Frandsen, S. (July 1998), ”Oscillation mode identifications and models for the delta Scuti star FG Virginis”, Astronomy & Astrophysics 335: 549–560, Bibcode: 1998A&A...335..549V.
Breger, M.; Zima, W.; Handler, G.; Poretti, E.; Shobbrook, R. R.; Nitta, A.; Prouton, O. R.; Garrido, R.; et al. (March 1998), ”The delta Scuti star FG Vir. III. The 1995 multisite campaign and the detection of 24 pulsation frequencies”, Astronomy & Astrophysics 331: 271–279, Bibcode: 1998A&A...331..271B.
Stankov, A.; Zima, W. (March 1998), ”Photometry of the Delta Scuti Star FG VIR during the 1995 Multi-Site Campaign”, Baltic Astronomy 7 (2): 243–253, doi:10.1515/astro-1998-0207, Bibcode: 1998BaltA...7..243S.
Breger, M.; Handler, G.; Serkowitsch, E.; Reegen, P.; Provencal, J.; Wood, M. A.; Clemens, J. C.; O'Brien, M. S.; et al. (May 1996), ”The δ Scuti star FG Virginis. II. A search for high pulsation frequencies”, Astronomy & Astrophysics 309: 197–202, Bibcode: 1996A&A...309..197B.
Guzik, J. A.; Bradley, P. A. (September 1995), ”Models and mode identifications of the Delta Scuti Star FG Vir”, Delta Scuti Star Newsletter 9 (9): 7–14, Bibcode: 1995DSSN....9....7G.
Breger, M. (September 1995), ”The 1995 FG VIR campaign: will 550 hours of new data and 19 frequencies be enough to do asteroseismology?”, Delta Scuti Star Newsletter 9 (9): 14–17, Bibcode: 1995DSSN....9...14B.
Dawson, D. W.; Breger, M.; Lopez de Coca, P. (June 1995), ”A Photometric Study of the delta Scuti Star FG Virginis Undertaken during 1985/6”, Publications of the Astronomical Society of the Pacific 107: 517–520, doi:10.1086/133585, Bibcode: 1995PASP..107..517D.
Dawson, D. W. (March 1990), ”The Period Structure of FG Virginis”, Bulletin of the American Astronomical Society 22: 831, Bibcode: 1990BAAS...22..831D.
Gonzalez-Bedolla, S. F.; Rodriguez, E. (February 1990), ”FG Vir, Additional Photoelectric Observations”, Information Bulletin on Variable Stars 3426: 1, Bibcode: 1990IBVS.3426....1G.

[B-1] 1 2 3 4 5 6 Brown, A. G. A.; et al. (Gaia collaboration) (2021), "Gaia Early Data Release 3: Summary of the contents and survey properties", Astronomy & Astrophysics, 649: A1, arXiv:2012.01533, Bibcode:2021A&A...649A...1G, doi:10.1051/0004-6361/202039657, S2CID 227254300 (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.

[C-2] 1 2 3 4 on", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.

[D-3] 1 2 3 Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.

[E-4] 1 2 Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Bibcode:1999MSS...C05....0H.

[F-5] 1 2 Rodríguez, E.; et al. (June 2000), "A revised catalogue of delta Sct stars", Astronomy & Astrophysics Supplement Series, 144 (3): 469–474, Bibcode:2000A&AS..144..469R, doi:10.1051/aas:2000221, hdl:10261/226673.

[G-6] 1 2 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.

[H-7] Breger, M.; Pamyatnykh, A. A. (May 2006), "Amplitude variability or close frequencies in pulsating stars - the δ Scuti star FG Vir", Monthly Notices of the Royal Astronomical Society, 368 (2): 571–578, arXiv:astro-ph/0602037, Bibcode:2006MNRAS.368..571B, doi:10.1111/j.1365-2966.2006.10119.x, S2CID 18429588.

[I-8] Zima, W.; et al. (June 2004), "Moment Method and Pixel-by-Pixel Method: Complementary Mode Identification I. Testing FG Vir-like pulsation modes", Communications in Asteroseismology, 144: 5–22, Bibcode:2004CoAst.144....5Z, doi:10.1553/cia144s5.

[J-9] Zima, W.; et al. (August 2006), "A new method for the spectroscopic identification of stellar non-radial pulsation modes. II. Mode identification of the δ Scuti star FG Virginis", Astronomy & Astrophysics, 455 (1): 235–246, arXiv:astro-ph/0606515, Bibcode:2006A&A...455..235Z, doi:10.1051/0004-6361:20064877, S2CID 54036626.

[K-10] 1 2 3 Breger, M.; Lenz, P. (February 2019), "Photometric data by the Delta Scuti Network. II. EE Cam, FG Vir, 44 Tau", The Journal of Astronomical Data, 25 (1): 6, Bibcode:2019JAD....25....1B.

[SIMBAD-11] ttps://simbad.cds.unistra.fr/simbad/sim-id?Ident=FG+Vir Arkiverad 15 januari 2026 hämtat från the Wayback Machine.. Hämtad 2025-12-25.

[L-12] "FG Vir", SIMBAD, Centre de données astronomiques de Strasbourg, hämtad 2022-06-14.

[M-13] Eitter, J. J.; Beavers, W. I. (June 1979), "Lunar occultation summary. III", Astrophysical Journal Supplement Series, 40: 475–486, Bibcode:1979ApJS...40..475E, doi:10.1086/190595. See event no. 528.

[A-14] 1 2 Breger, M.; et al. (May 1995), "The δ Scuti star FG Virginis. I. Multiple pulsation frequencies determined with a combined DSN/WET campaign", Astronomy & Astrophysics, 297: 473, Bibcode:1995A&A...297..473B.

[N-15] Eggen, O. J. (December 1971), "The Nature of the Blue Stragglers in the Old Disk Population", Publications of the Astronomical Society of the Pacific, 83 (496): 762, Bibcode:1971PASP...83..762E, doi:10.1086/129212, S2CID 120025134.

[O-16] Baglin, A.; et al. (March 1973), "Delta Scuti stars", Astronomy & Astrophysics, 23: 221, Bibcode:1973A&A....23..221B.

[P-17] Lopez de Coca, P.; et al. (January 1984), "Narrow Band Photometry of FG Vir", Information Bulletin on Variable Stars, 2465: 1, Bibcode:1984IBVS.2465....1L.

[Q-18] Mantegazza, L.; et al. (July 1994), "Simultaneous intensive photometry and high resolution spectroscopy of δ Scuti stars I. Mode typing of HD 106384 = FG Virginis", Astronomy & Astrophysics, 287: 95–104, Bibcode:1994A&A...287...95M.

[R-19] Breger, M.; et al. (January 1999), "The delta Scuti star FG Virginis. IV. Mode identifications and pulsation modelling", Astronomy & Astrophysics, 341: 151–162, arXiv:astro-ph/9811338, Bibcode:1999A&A...341..151B.

[S-20] Breger, M.; et al. (June 2005), "Detection of 75+ pulsation frequencies in the δ Scuti star FG Virginis", Astronomy & Astrophysics, 435 (3): 955–965, arXiv:astro-ph/0502073, Bibcode:2005A&A...435..955B, doi:10.1051/0004-6361:20042480, S2CID 119042031.

[T-21] Mittermayer, P.; Weiss, W. W. (September 2003), "Atmospheric properties and abundances of the delta Scuti star FG Virginis", Astronomy & Astrophysics, 407 (3): 1097–1101, Bibcode:2003A&A...407.1097M, doi:10.1051/0004-6361:20030930, S2CID 123022971.