V471 Tauri

V471 Tauri

A light curve for V471 Tauri, plotted from TESS data
Observation data
Epoch J2000      Equinox J2000
Constellation Taurus
Right ascension 03h 50m 24.9667s
Declination 17° 14′ 47.431″
Apparent magnitude (V) 9.40 - 9.71
Characteristics
Evolutionary stage main sequence + white dwarf
Spectral type K2V + D2
Variable type Algol + RS CVn
Astrometry
Radial velocity (Rv)37.4±0.5 km/s
Proper motion (μ) RA: 127.278 mas/yr
Dec.: −22.321 mas/yr
Parallax (π)21.0129±0.0158 mas
Distance155.2 ± 0.1 ly
(47.59 ± 0.04 pc)
Orbit
Period (P)0.52118 days
Semi-major axis (a)0.01496 AU
Eccentricity (e)0 (assumed)
Inclination (i)80.8°
Details
White dwarf
Mass0.792 M☉
Radius0.01134 R☉
Luminosity0.145 L☉
Surface gravity (log g)8.227 cgs
Temperature34,500 K
K star
Mass0.852 M☉
Radius0.816 R☉
Luminosity0.41 L☉
Surface gravity (log g)4.49 cgs
Temperature5,066 K
Metallicity [Fe/H]+0.12 dex
Rotation0.5211 days
Rotational velocity (v sin i)89.30 km/s
Age625 Myr
Other designations
471 Tau, BD+16°516, HIP 17962
Database references
SIMBADdata

V471 Tauri (short V471 Tau) is an eclipsing variable star in the constellation of Taurus. The star has a visual magnitude of 9 which makes it impossible to see with the naked eye. It is around 155 light-years away from the Solar System, in the Hyades star cluster.

In 1970, Burt Nelson and Arthur Young announced that the star is a variable star. It was given its variable star designation in 1972.

Physical properties

The V471 Tauri system has at least two members: a white dwarf star of spectral type D2; and a K-type main sequence star (K2 V), together a post-common envelope binary. There are variations in the timing of the eclipses that were once thought to be due to a third member of the system, proposed to be a brown dwarf, but a direct imaging search for this object with SPHERE resulted in a non-detection. The eclipse variations may be caused by the Applegate mechanism, or the third body may be a pair of smaller brown dwarfs, which would be too faint to have been detected. Later studies have found that the timing variations cannot be explained solely by additional components of the system; even if one or more brown dwarfs are present, the Applegate mechanism must also be a factor.

References

  1. ↑ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
  2. 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.
  3. 1 2 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.
  4. 1 2 Hussain, G. A. J.; Allende Prieto, C.; Saar, S. H.; Still, M. (2006). "Spot patterns and differential rotation in the eclipsing pre-cataclysmic variable binary, V471 Tau". Monthly Notices of the Royal Astronomical Society. 367 (4): 1699–1708. arXiv:astro-ph/0602562. Bibcode:2006MNRAS.367.1699H. doi:10.1111/j.1365-2966.2006.10073.x. S2CID 15303415.
  5. ↑ Karataș, Yüksel; Bilir, Selçuk; Eker, Zeki; Demircan, Osman; Liebert, James; Hawley, Suzanne L.; Fraser, Oliver J.; Covey, Kevin R.; Lowrance, Patrick; Kirkpatrick, J. Davy; Burgasser, Adam J. (2004). "Kinematics of chromospherically active binaries and evidence of an orbital period decrease in binary evolution". Monthly Notices of the Royal Astronomical Society. 349 (3): 1069–1092. arXiv:astro-ph/0404219. Bibcode:2004MNRAS.349.1069K. doi:10.1111/j.1365-2966.2004.07588.x. S2CID 15290475.
  6. 1 2 3 4 5 6 7 8 Muirhead, Philip S.; Nordhaus, Jason; Drout, Maria R. (2022). "Revised Stellar Parameters for V471 Tau, A Post-common Envelope Binary in the Hyades". The Astronomical Journal. 163 (1): 34. arXiv:2111.06905. Bibcode:2022AJ....163...34M. doi:10.3847/1538-3881/ac390f. S2CID 244116994.
  7. 1 2 3 Vaccaro, T. R.; Wilson, R. E.; Van Hamme, W.; Terrell, Dirk (2015). "The V471 Tauri System: A Multi-data-type Probe". The Astrophysical Journal. 810 (2): 157. arXiv:1506.05067. Bibcode:2015ApJ...810..157V. doi:10.1088/0004-637X/810/2/157. S2CID 119256081.
  8. 1 2 3 Kővári, Zs; Kriskovics, L.; Oláh, K.; Odert, P.; Leitzinger, M.; Seli, B.; Vida, K.; Borkovits, T.; Carroll, T. (2021). "A confined dynamo: Magnetic activity of the K-dwarf component in the pre-cataclysmic binary system V471 Tauri". Astronomy and Astrophysics. 650: A158. arXiv:2103.02041. Bibcode:2021A&A...650A.158K. doi:10.1051/0004-6361/202140707. S2CID 232105205.
  9. 1 2 3 4 Zaire, B.; Donati, J. -F.; Klein, B. (2021). "Magnetic field and activity phenomena of the K2 dwarf V471 Tau". Monthly Notices of the Royal Astronomical Society. 504 (2): 1969. arXiv:2104.02619. Bibcode:2021MNRAS.504.1969Z. doi:10.1093/mnras/stab1019.
  10. ↑ Nelson, Burt; Young, Arthur (June 1970). "A New Eclipsing Binary Containing a Very Hot White Dwarf". Publications of the Astronomical Society of the Pacific. 82 (487): 699–706. Bibcode:1970PASP...82..699N. doi:10.1086/128946. Retrieved 4 September 2025.
  11. ↑ Kukarkin, B. V.; Kholopov, P. N.; Kukarkina, N. P.; Perova, N. B. (September 1972). "58th Name-List of Variable Stars" (PDF). Information Bulletin on Variable Stars. 717: 1–36. Bibcode:1972IBVS..717....1K. Retrieved 4 September 2025.
  12. ↑ "The Strange Case of the Missing Dwarf". ESO. 18 February 2015. Retrieved 20 December 2024.
  13. ↑ Hardy, A.; Schreiber, M. R.; et al. (February 2015). "The First Science Results from Sphere: Disproving the Predicted Brown Dwarf Around V471 Tau". The Astrophysical Journal Letters. 800 (2): L24. arXiv:1502.05116. Bibcode:2015ApJ...800L..24H. doi:10.1088/2041-8205/800/2/L24.
  14. ↑ Kundra, Emil; Hambálek, Ľubomír; et al. (December 2022). "Variability of eclipse timing: the case of V471 Tauri". Monthly Notices of the Royal Astronomical Society. 517 (4): 5358–5367. arXiv:2210.01464. Bibcode:2022MNRAS.517.5358K. doi:10.1093/mnras/stac2812.