HD 283750


Coordinates: Sky map 04h 36m 48.2413s, +27° 07′ 55.8983″

HD 283750
Observation data
Epoch J2000      Equinox J2000
Constellation Taurus
Right ascension 04h 36m 48.2413s[1]
Declination 27° 07′ 55.8983″[1]
Evolutionary stage Main sequence
Spectral type K5Ve[2]
B−V color index 1.12[2]
Variable type BY Draconis
Radial velocity (Rv)42±3[3] km/s
Proper motion (μ) RA: 232.17±0.06[3] mas/yr
Dec.: -147.48±0.04[3] mas/yr
Parallax (π)57.49 ± 0.05[3] mas
Distance56.73 ± 0.05 ly
(17.39 ± 0.02 pc)
Mass0.8 M
Radius0.8 R
Surface gravity (log g)4.5 cgs
Temperature4250±100 K
Rotational velocity (v sin i)7.4 km/s
Age1[4] Gyr
Other designations
V833 Tauri, BD+26 730, Gaia DR2 151650076838458112, GJ 171.2, HIP 21482, TYC 1838-564-1, 2MASS J04364822+2707559[1]
Database references

HD 283750, also known as V833 Tauri, is a K-type main-sequence star 56.73±0.05 light-years away from the Sun. The star's age is much younger than the Sun's at 1 billion years.[4] HD 283750 is similar to the Sun in its concentration of heavy elements.[2]

The star has a co-moving white dwarf companion WD 0443+270 at a projected separation of 124″,[5] both possibly ejected members of the Hyades cluster. The white dwarf companion has a rather exotic iron core[4] and belongs to spectral class DA9 and has the mass of 0.62±0.02M.[6]

Although HD 283750 was classified as a multi-period variable,[7] a paper in 2020 claims its variability is not exceeding the variability of the Sun, and no period can be identified.[8]

HD 283750 is covered by a large amount of starspots, filling up to 28% of the stellar surface at the maxima of the magnetic cycle.[9] In November 1993, the star emitted an extremely powerful flare with energy of 7.47×1034 ergs, which is on or even above the upper limit of possible energy releases in flare stars.[7] The flares of HD 283750 are accompanied by particle beams strong enough to affect the polarization properties of the stellar photosphere.[10]

Suspected substellar companion

In 1996 a suspected 50-MJ brown dwarf HD 283750b on a 1.79-days orbit around HD 283750 was detected by the differential Doppler spectroscopy method. By 2007, the mass of the companion was refined to 0.19M, making it a red dwarf star.[11]


  1. ^ a b c "HD 283750". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 30 June 2021.
  2. ^ a b c d Naftilan, S. A.; Fairchild, K. (1993). "Abundance Analysis of the BY Draconis Variable, Hot Flare Star V833 Tauri". Publications of the Astronomical Society of the Pacific. 105: 565. doi:10.1086/133194.
  3. ^ a b c 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. Gaia EDR3 record for this source at VizieR.
  4. ^ a b c Catalán, S.; Ribas, I.; Isern, J.; García-Berro, E. (2007), "WD0433+270: An old Hyades stream member or an Fe-core white dwarf?", Astronomy & Astrophysics, 477 (3): 901–906, arXiv:0710.3999, doi:10.1051/0004-6361:20078230, S2CID 1559222
  5. ^ Scholz, R.-D.; Meusinger, H.; Jahreiß, H. (2018), "New nearby white dwarfs from Gaia DR1 TGAS and UCAC5/URAT", Astronomy & Astrophysics, 613: A26, arXiv:1711.10778, Bibcode:2018A&A...613A..26S, doi:10.1051/0004-6361/201731753, S2CID 59423840
  6. ^ Toonen, S.; Hollands, M.; Gänsicke, B. T.; Boekholt, T. (2017), "The binarity of the local white dwarf population", Astronomy & Astrophysics, 602: A16, arXiv:1703.06893, Bibcode:2017A&A...602A..16T, doi:10.1051/0004-6361/201629978, S2CID 12367523
  7. ^ a b Oláh, K.; Strassmeier, K. G.; Kővári, Zs.; Guinan, E. F. (2001). "Time-series photometric spot modeling. IV. The multi-periodic K5Ve binary V833 Tauri". Astronomy & Astrophysics. 372: 119–129. Bibcode:2001A&A...372..119O. doi:10.1051/0004-6361:20010362.
  8. ^ Frick, P.; Sokoloff, D.; Katsova, M. M.; Bondar', N. I.; Stepanov, R. (2020). "Wavelet analysis of the long-term activity of V833 Tau". Monthly Notices of the Royal Astronomical Society. 495 (4): 3788–3794. arXiv:2005.11136. doi:10.1093/mnras/staa1458.
  9. ^ Bondar', N. I. (2017). "Photometric period and rotational brightness modulation of V833 Tau". Astronomy Reports. 61 (2): 130–137. Bibcode:2017ARep...61..130B. doi:10.1134/S1063772917010024. S2CID 126233507.
  10. ^ Saar, S. H.; Martens, P. C. H.; Huovelin, J.; Linnaluoto, S. (1994). "Possible detection of a stellar flare-generated particle beam in polarized light". Astronomy and Astrophysics. 286: 194. Bibcode:1994A&A...286..194S.
  11. ^ Bonavita, M.; Desidera, S.; Thalmann, C.; Janson, M.; Vigan, A.; Chauvin, G.; Lannier, J. (2016). "SPOTS: The Search for Planets Orbiting Two Stars II. First constraints on the frequency of sub-stellar companions on wide circumbinary orbits". Astronomy and Astrophysics. 593: 593. arXiv:1605.03962. Bibcode:2016A&A...593A..38B. doi:10.1051/0004-6361/201628231. S2CID 55950739.