V1054 Ophiuchi

V1054 Ophiuchi

An ultraviolet band light curve for a flare on V1054 Ophiuchi, plotted from data published by Dal and Evren (2010)
Observation data
Epoch J2000      Equinox ICRS
Constellation Ophiuchus
AB
Right ascension 16h 55m 28.75757s
Declination −08° 20′ 10.7878″
Apparent magnitude (V) 9.74/10.34/10.84
Gliese 643
Right ascension 16h 55m 25.22225s
Declination −08° 19′ 21.2970″
Apparent magnitude (V) 11.74
C (VB 8)
Right ascension 16h 55m 35.25574s
Declination −08° 23′ 40.7531″
Apparent magnitude (V) 16.80
Characteristics
AB
Spectral type M3 V / M4 Ve
Gliese 643
Spectral type M3.5 V
C (VB 8)
Spectral type M7.0 V
Astrometry
AB
Radial velocity (Rv)14.89±0.05 km/s
Proper motion (μ) RA: −817.84±6.68 mas/yr
Dec.: −873.53±3.53 mas/yr
Parallax (π)161.41±5.64 mas
Distance20.2 ± 0.7 ly
(6.2 ± 0.2 pc)
Absolute magnitude (MV)10.23
Gliese 643
Radial velocity (Rv)15.20±0.15 km/s
Proper motion (μ) RA: −817.580(52) mas/yr
Dec.: −898.595(40) mas/yr
Parallax (π)153.8754±0.0474 mas
Distance21.196 ± 0.007 ly
(6.499 ± 0.002 pc)
Absolute magnitude (MV)12.60
VB 8
Proper motion (μ) RA: −813.038(63) mas/yr
Dec.: −870.609(44) mas/yr
Parallax (π)153.9659±0.0570 mas
Distance21.184 ± 0.008 ly
(6.495 ± 0.002 pc)
Absolute magnitude (MV)17.75
Orbit
PrimaryV1054 Oph A
SecondaryV1054 Oph B
Period (P)1.71741±0.00005 yr
Semi-major axis (a)0.22949±0.00046″
Eccentricity (e)0.04225±0.00092
Inclination (i)161.30±0.49°
Longitude of the node (Ω)164.7±1.6°
Periastron epoch (T)1991.6311±0.0063
Argument of periastron (ω)
(secondary)		128.7±3.3°
Orbit
PrimaryV1054 Oph Ba
SecondaryV1054 Oph Bb
Period (P)2.965509±0.000006 d
Semi-major axis (a)0.00687"
(0.04432 AU)
Eccentricity (e)0.0209±0.0008
Inclination (i)164.18±0.08°
Periastron epoch (T)MJD 50919.48±0.03
Argument of periastron (ω)
(secondary)		150.0±3.0°
Details
A
Mass0.4155±0.0057 M☉
Radius0.533±0.021 R☉
Luminosity0.02 L☉
Surface gravity (log g)4.7083 ± 0.0145 cgs
Temperature3,537±67 K
Ba
Mass0.3466±0.0047 M☉
Bb
Mass0.3143±0.0040 M☉
Gliese 643
Mass0.207±0.010 M☉
Radius0.282+0.002
−0.005 R☉
Luminosity0.005303+0.000004
−0.000005 L☉
Surface gravity (log g)4.488 ± 0.006 cgs
Temperature3,028+4
−5 K
Metallicity [Fe/H]-0.794 ± 0.008 dex
C (VB 8)
Mass0.0914+0.0026
−0.0025 M☉
Radius0.1214+0.0060
−0.0057 R☉
Luminosity0.000645+0.000004
−0.000005 L☉
Temperature2,640+65
−64 K
Rotation11.19±0.02 days
Other designations
CCDM J16555-0820
AB: V1054 Oph, BD−08°4352, GJ 644, HD 152751, HIP 82817, SAO 141439, LHS 428, Wolf 630
GJ 643: GJ 643, HIP 82809, LHS 427, Wolf 629
C: GJ 644 C, LHS 429, VB 8
Database references
SIMBADABab
GJ 643
C (vB 8)

V1054 Ophiuchi, together with the star Gliese 643, is a nearby quintuple star system, located in the constellation Ophiuchus at a distance of 21.2 light-years (6.5 parsecs). It consists of five stars, all of which are red dwarfs. The alternative designation of Wolf 630 forms the namesake of a moving group of stars that share a similar motion through space.

Overview

A
P = 1.72 yr
Ba
P = 2.97 d
Bb
72″ separation
GJ 643
220″ separation
C (VB 8)

Hierarchy of orbits in the system

V1054 Ophiuchi/Gliese 643 is the nearest quintuple star system; the next nearest star systems with at least five stars are Xi Ursae Majoris (quintuple, including a brown dwarf) at 28.5 light-years, Castor (sextuple) at 49.2 light-years, and GJ 2069 (quintuple) at 54.3 light-years. V1054 Ophiuchi and Xi Ursae Majoris are the only two quintuple star systems within 10 parsecs.

The system consists of three widely separated parts:

The brightest and most massive of these five stars is V1054 Ophiuchi A. The close binary subsystem V1054 Ophiuchi B is more massive than V1054 Ophiuchi A, however, its total visual magnitude is 0.1 mag fainter than V1054 Ophiuchi A's visual magnitude.

The total apparent magnitude of the V1054 Ophiuchi A-Bab triple subsystem is 9.02.

Despite V1054 Ophiuchi/Gliese 643 consisting of low-mass stars, the system's total mass, due to the large number of components, exceeds the Solar mass, about 1.35 M☉.

Distance

Currently, the most accurate distance estimate of V1054 Ophiuchi/Gliese 643 is a trigonometric parallax of Gliese 643 from Gaia DR3: 153.8754±0.0474 mas, corresponding to a distance of 6.499±0.002 pc, or 21.196±0.007 ly.

Past V1054 Ophiuchi/Gliese 643 distance estimates

V1054 Ophiuchi A-Bab:

SourcePaperParallax, masDistance, pcDistance, lyRef.
WoolleyWoolley et al. 1970156 ± 46.41 ± 0.1720.9 ± 0.6
GJ, 3rd versionGliese & Jahreiß 1991153.9 ± 2.66.50 ± 0.1121.19 ± 0.36
YPC, 4th editionvan Altena et al. 1995154.8 ± 0.66.460 ± 0.02521.07 ± 0.08
HipparcosPerryman 1997174.23 ± 3.905.74 ± 0.1318.7 ± 0.4
SoederhjelmSoederhjelm 1999155.63 ± 1.816.43 ± 0.0820.96 ± 0.25
Hipparcos2van Leeuwen 2007161.41 ± 5.646.20 ± 0.2220.21 ± 0.73

Gliese 643:

SourcePaperParallax, masDistance, pcDistance, lyRef.
WoolleyWoolley et al. 1970169 ± 55.92 ± 0.1819.3 ± 0.6
GJ, 3rd versionGliese & Jahreiß 1991171.9 ± 7.35.82 ± 0.2619.0 ± 0.8
YPC, 4th editionvan Altena et al. 1995169.8 ± 6.65.89 ± 0.2419.2 ± 0.8
HipparcosPerryman 1997153.96 ± 4.046.50 ± 0.1821.2 ± 0.6
Hipparcos2van Leeuwen 2007148.92 ± 4.006.72 ± 0.1921.9 ± 0.6

V1054 Ophiuchi C (vB 8):

SourcePaperParallax, masDistance, pcDistance, lyRef.
CTIOPI 1.5 mTSN 14 (Costa et al. 2005)155.43 ± 1.336.43 ± 0.0620.98 ± 0.18

Weighted mean distance

A weighted mean parallax was calculated by RECONS in 2012, considering YPC (V1054 Ophiuchi A-Bab and Gliese 643), Hipparcos (Soederhjelm — V1054 Ophiuchi A-Bab and van Leeuwen — Gliese 643) and CTIOPI (V1054 Ophiuchi C) data. The value is 154.96±0.52 mas, corresponding to a distance of 6.453±0.022 pc, or 21.05±0.07 ly. This predates Gaia astrometry of the system.

System

V1054 Ophiuchi A-Bab (inner triple subsystem)

V1054 Ophiuchi A-Bab is a close spectroscopic triple subsystem, consisting of the brighter component V1054 Ophiuchi A and the more massive binary subsystem V1054 Ophiuchi Bab, orbiting each other with a period of 627 days, or 1.72 years. V1054 Ophiuchi Bab components are orbiting each other with a period of 2.9655 days. Both outer and inner orbits are nearly circular and, probably, coplanar (in keeping with a general tendency of close triple systems).

V1054 Ophiuchi A-Bab pair is also visually resolved (for nearly 50 years it was the shortest-period resolved by visual means binary, since its binarity was discovered by G. P. Kuiper in 1934), whereas V1054 Ophiuchi Ba-Bb pair is still unresolved).

Gliese 643

The projected separation of Gliese 643 from V1054 Ophiuchi A-Bab is 72 arcsec, corresponding at 21.05 light-years to 465 AU.

V1054 Ophiuchi C (vB 8)

vB 8 is the smallest, faintest, and most separated component of the V1054 Ophiuchi system. The projected separation of the red dwarf from the primary triple system is about 220 arcsec, corresponding at 21.05 light-years to 1420 a.u. Since it is only three times larger than the projected separation between Gliese 643 and V1054 Ophiuchi A-Bab, and such a small ratio should render the triple system dynamically unstable, it was suggested that the real separation of V1054 Ophiuchi C from V1054 Ophiuchi A-Bab is much larger, at least by a factor of two, i. e. at least 2840 a.u.

In 1984, the apparent detection of an infrared source near vB 8 suggested it had a low mass companion. The low mass of this candidate led to speculation that it may be a brown dwarf; the first such to be detected. This discovery was later found to be spurious, but it produced much interest in this class of astronomical object.

Notes

  1. ↑ Referred to entire V1054 Ophiuchi Bab subsystem.
  2. ↑ From masses, period and parallax.
  3. ↑ From masses and period. According to Mazeh et al. 2001, of order of 0.05 a. u.
  4. ↑ At least it was not resolved by 2001.

References

  1. ↑ Dal, H. A.; Evren, S. (August 2010). "A New Method for Classifying Flares of UV Ceti Type Stars: Differences Between Slow and Fast Flares". The Astronomical Journal. 140 (2): 483–489. arXiv:1206.5791. Bibcode:2010AJ....140..483D. doi:10.1088/0004-6256/140/2/483. S2CID 119308060.
  2. 1 2 3 4 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.
  3. 1 2 3 4 5 6 7 Vizier, Hipparcos, the New Reduction (van Leeuwen 2007)
  4. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Mazeh, Tsevi; Latham, David W.; Goldberg, Elad; Torres, Guillermo; Stefanik, Robert P.; Henry, Todd J.; Zucker, Shay; Gnat, Orly; Ofek, Eran O. (2001). "Studies of multiple stellar systems - IV. The triple-lined spectroscopic system V1054 Ophiuchi". Monthly Notices of the Royal Astronomical Society. 325 (1): 343–357. arXiv:astro-ph/0102451. Bibcode:2001MNRAS.325..343M. doi:10.1046/j.1365-8711.2001.04419.x. S2CID 16472347.
  5. 1 2 3 4 5 6 7 8 9 10 11 12 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  6. 1 2 3 4 5 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  7. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Ségransan, Damien; Delfosse, Xavier; Forveille, Thierry; Beuzit, Jean-Luc; Udry, Stéphane; Perrier, Christian; Mayor, Michel (2000). "Accurate masses of very low mass stars. III. 16 new or improved masses". Astronomy and Astrophysics. 364: 665–673. arXiv:astro-ph/0010585. Bibcode:2000A&A...364..665S.
  8. ↑ Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; Levato, H.; Morrell, N. I.; Torres, G.; Udry, S. (2004). "SB9: The ninth catalogue of spectroscopic binary orbits". Astronomy and Astrophysics. 424: 727. arXiv:astro-ph/0406573. Bibcode:2004A&A...424..727P. doi:10.1051/0004-6361:20041213.
  9. ↑ Mason, Brian D.; Tokovinin, Andrei; Mendez, Rene A.; Costa, Edgardo (October 2023). "Speckle Interferometry at SOAR in 2022". The Astronomical Journal. 166 (4): 139. arXiv:2405.10071. Bibcode:2023AJ....166..139M. doi:10.3847/1538-3881/acedaf. ISSN 0004-6256.
  10. 1 2 Stassun, Keivan G.; Oelkers, Ryan J.; Paegert, Martin; Torres, Guillermo; Pepper, Joshua; De Lee, Nathan; Collins, Kevin; Latham, David W.; Muirhead, Philip S.; Chittidi, Jay; Rojas-Ayala, Bárbara; Fleming, Scott W.; Rose, Mark E.; Tenenbaum, Peter; Ting, Eric B. (2019-10-01). "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. ISSN 0004-6256. S2CID 166227927.
  11. ↑ 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.
  12. ↑ González-Payo, J.; Caballero, J.; Cifuentes, C; Cortés-Contreras, M.; Rica, F. (7 May 2026). "Characterisation of all known multiple stellar systems within 10 pc". Monthly Notices of the Royal Astronomical Society. 549 (1) stag838. arXiv:2605.04094. Bibcode:2026MNRAS.549ag838G. doi:10.1093/mnras/stag838.
  13. 1 2 3 4 Pineda, J. Sebastian; Youngblood, Allison; France, Kevin (September 2021). "The M-dwarf Ultraviolet Spectroscopic Sample. I. Determining Stellar Parameters for Field Stars". The Astrophysical Journal. 918 (1): 23. arXiv:2106.07656. Bibcode:2021ApJ...918...40P. doi:10.3847/1538-4357/ac0aea. S2CID 235435757. 40.
  14. ↑ Kemmer, J.; Lafarga, M.; Fuhrmeister, B.; Shan, Y.; Schöfer, P.; Jeffers, S. V.; Caballero, J. A.; Quirrenbach, A.; Amado, P. J. (2025-04-11). "The CARMENES search for exoplanets around M dwarfs. Cluster analysis of signals from spectral activity indicators to search for shared periods". Astronomy and Astrophysics. 697. arXiv:2504.08363. Bibcode:2025A&A...697A.225K. doi:10.1051/0004-6361/202347056.
  15. ↑ "HD 152751". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-03-25.
  16. ↑ "GJ 643". SIMBAD. Centre de données astronomiques de Strasbourg.
  17. ↑ "VB 8". SIMBAD. Centre de données astronomiques de Strasbourg.
  18. ↑ Bubar, Eric J.; King, Jeremy R. (August 2010). "Spectroscopic Abundances and Membership in the Wolf 630 Moving Group". The Astronomical Journal. 140 (2): 293–318. arXiv:1005.1205. Bibcode:2010AJ....140..293B. doi:10.1088/0004-6256/140/2/293. S2CID 118455341.
  19. 1 2 Reylé, Céline; Jardine, Kevin; Fouqué, Pascal; Caballero, Jose A.; Smart, Richard L.; Sozzetti, Alessandro (30 April 2021). "The 10 parsec sample in the Gaia era". Astronomy & Astrophysics. 650: A201. arXiv:2104.14972. Bibcode:2021A&A...650A.201R. doi:10.1051/0004-6361/202140985. S2CID 233476431. Data available at https://gruze.org/10pc/ Archived 12 March 2023 at the Wayback Machine
  20. 1 2 3 Vizier, The Hipparcos and Tycho Catalogues (ESA 1997)
  21. 1 2 Vizier, Stars within 25 pc of the Sun (Woolley+ 1970)
  22. 1 2 Vizier, Nearby Stars, Preliminary 3rd Version (Gliese+ 1991)
  23. 1 2 VizieR, Yale Trigonometric Parallaxes, Fourth Edition (van Altena+ 1995)
  24. ↑ Vizier, Visual binary orbits and masses (Soederhjelm 1999)
  25. ↑ Costa, Edgardo; Méndez, René A.; Jao, W.-C.; Henry, Todd J.; Subasavage, John P.; Brown, Misty A.; Ianna, Philip A.; Bartlett, Jennifer (2005). "The Solar Neighborhood. XIV. Parallaxes from the Cerro Tololo Inter-American Observatory Parallax Investigation-First Results from the 1.5 m Telescope Program". The Astronomical Journal. 130 (1): 337–349. Bibcode:2005AJ....130..337C. CiteSeerX 10.1.1.573.7563. doi:10.1086/430473. S2CID 12213270. {{cite journal}}: Cite uses deprecated parameter |citeseerx= (help)
  26. ↑ DENSE Project. 25 pc White Dwarf Sample Archived 2012-04-01 at the Wayback Machine (see formulae below)
  27. ↑ THE ONE HUNDRED NEAREST STAR SYSTEMS brought to you by RECONS (Research Consortium On Nearby Stars)
  28. ↑ Reid, Neill I.; Hawley, Suzanne L. (27 November 2013). New Light on Dark Stars: Red Dwarfs, Low-Mass Stars, Brown Dwarfs. Astronomy and Planetary Sciences. Springer Science & Business Media, 2013. p. 344. ISBN 978-1447136637.