7 Tauri

Summary

7 Tauri is a multiple star in the northern constellation of Taurus. It has a combined apparent visual magnitude of 5.95,[10] so, according to the Bortle scale, it is faintly visible from suburban skies at night. Measurements made with the Gaia spacecraft show an annual parallax shift of 5.5 mas, which is equivalent to a distance of around 593 light years from the Sun.

7 Tauri
Observation data
Epoch J2000      Equinox J2000
Constellation Taurus
A
Right ascension 03h 34m 26.629s[1]
Declination +35° 27′ 51.86″[1]
Apparent magnitude (V) 6.58[2]
B
Right ascension 03h 34m 26.633s[3]
Declination +35° 27′ 52.17″[3]
Apparent magnitude (V) 6.84[2]
Characteristics
A
Spectral type A3V[4]
B−V color index +0.13[4]
B
Spectral type A3V[4]
B−V color index +0.13[4]
Astrometry
Radial velocity (Rv)+28.1[5] km/s
Proper motion (μ) RA: +9.908 mas/yr[1]
Dec.: −28.201 mas/yr[1]
Parallax (π)5.4993 ± 0.0587 mas[1]
Distance593 ± 6 ly
(182 ± 2 pc)
Absolute magnitude (MV)+0.5/+0.6[4]
Orbit[6]
Period (P)522.16 yr
Semi-major axis (a)0.625″
Eccentricity (e)0.679
Details
A
Mass2.5[4] M
Radius9.0[7] R
Luminosity52[7] L
Temperature8,551[8] K
B
Mass2.5[4] M
Other designations
7 Tau, BD+23°473, HD 22091, HIP 16664, HR 1086[9]
Database references
SIMBADdata

7 Tauri is a binary star with two nearly equal components about 0.7 apart, designated as A and B. The spectrum of each star matches a stellar classification of A7V.[4]22″ away is a 10th-magnitude star, component C, which is itself a spectroscopic binary. In the past, these stars had been treated as a single system, but they are now known to have different proper motions and somewhat different distances.[4]

References edit

  1. ^ a b c d 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.
  2. ^ a b Fabricius, C.; Høg, E.; Makarov, V. V.; Mason, B. D.; Wycoff, G. L.; Urban, S. E. (March 2002). "The Tycho double star catalogue". Astronomy & Astrophysics. 384 (1): 180–189. Bibcode:2002A&A...384..180F. doi:10.1051/0004-6361:20011822. ISSN 0004-6361.
  3. ^ a b 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.
  4. ^ a b c d e f g h i Tokovinin, A. A. (1998). "New spectroscopic components in six multiple systems". Astronomy Letters. 24 (3): 288. Bibcode:1998AstL...24..288T.
  5. ^ Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. ISSN 1063-7737. S2CID 119231169.
  6. ^ Malkov, O. Yu.; et al. (2012). "Dynamical Masses of a Selected Sample of Orbital Binaries". Astronomy & Astrophysics. 546: 5. Bibcode:2012A&A...546A..69M. doi:10.1051/0004-6361/201219774. A69.
  7. ^ a b 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.
  8. ^ Stassun, Keivan G.; Oelkers, Ryan J.; Pepper, Joshua; Paegert, Martin; De Lee, Nathan; Torres, Guillermo; Latham, David W.; Charpinet, Stéphane; Dressing, Courtney D.; Huber, Daniel; Kane, Stephen R.; Lépine, Sébastien; Mann, Andrew; Muirhead, Philip S.; Rojas-Ayala, Bárbara; Silvotti, Roberto; Fleming, Scott W.; Levine, Al; Plavchan, Peter; the TESS Target Selection Working Group (2018). "The TESS Input Catalog and Candidate Target List". The Astronomical Journal. 156 (3): 102. arXiv:1706.00495. Bibcode:2018AJ....156..102S. doi:10.3847/1538-3881/aad050. S2CID 73582386.
  9. ^ "7 Tau". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2022-09-20.
  10. ^ Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.