Delta3 Tauri


Delta3 Tauri
Taurus IAU.svg
Red circle.svg
Location of δ3 Tauri (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Taurus
Right ascension 04h 25m 29.38340s[1]
Declination +17° 55′ 40.4579″[1]
Apparent magnitude (V) +4.32 (4.35 + 8.37)[2]
Spectral type A2IV
Proper motion (μ) RA: +41.91[1] mas/yr
Dec.: −34.54[1] mas/yr
Parallax (π)21.96 ± 0.51[1] mas
Distance149 ± 3 ly
(46 ± 1 pc)
Absolute magnitude (MV)+1.14[3]
Mass2.27±0.23[4] M
Luminosity1.47±0.05[4] L
Surface gravity (log g)3.95[4] cgs
Temperature9,025[4] K
Rotational velocity (v sin i)11.3[4] km/s
Other designations
Cleeia, δ3 Tau, 68 Tauri, BD+17°719, HD 27962, HIP 20648, HR 1389, SAO 93923, ADS 3206[5]
Database references

Delta3 Tauri (δ3 Tauri) is a binary star[2] system in the zodiac constellation of Taurus. Based upon an annual parallax shift of 21.96 mas as seen from Earth,[1] it is located roughly 149 light years distant from the Sun. It is visible to the naked eye with a combined apparent visual magnitude of +4.32.[2] δ3 Tauri is separated from δ1 Tauri by 0.72° on the sky.[5] This star also has the traditional Latin name Cleeia,[6][7] from the Greek Kleeia (transliteration of Κλεεια),[8] who was one of the Hyades sisters. It is considered a member of the Hyades cluster.[4]

In Chinese, 畢宿 (Bì Xiù), meaning Net, refers to an asterism consisting δ3 Tauri, ε Tauri, δ1 Tauri, γ Tauri, Aldebaran, 71 Tauri and λ Tauri.[9] Consequently, the Chinese name for δ3 Tauri itself is 畢宿二 (Bì Xiù èr), "the Second Star of Net".[10]

The magnitude 4.35[2] primary, component A, appears to be an A-type subgiant star with a stellar classification of A2 IV. It is a candidate blue straggler and shows characteristics of an Am star. Abt (1985) gave it a classification of A2kA3hA5m, indicating that the spectrum displays the calcium K-line of an A2 star, the hydrogen lines of an A3 star and the metal lines of an A5 star. It is deficient in scandium but has enhanced iron peak and heavy elements.[4] Although suspect of variability in the past,[11] Delta3 Tauri A was subsequently determined to be photometrically constant.[12]

The companion, component B, is a magnitude 8.37[2] star at an angular separation of 1.80 arc seconds along a position angle of 341°, as of 2010. At 77 arcseconds away (as of 2006) is a magnitude 11.12 visual companion, designated component C.[13]


  1. ^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
  2. ^ a b c d e Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  3. ^ Eggen, Olin J. (July 1998), "The Age Range of Hyades Stars", The Astronomical Journal, 116 (1): 284–292, Bibcode:1998AJ....116..284E, doi:10.1086/300413.
  4. ^ a b c d e f g Gebran, M.; Vick, M.; Monier, R.; Fossati, L. (November 2010), "Chemical composition of A and F dwarfs members of the Hyades open cluster", Astronomy and Astrophysics, 523: 13, arXiv:1006.5284, Bibcode:2010A&A...523A..71G, doi:10.1051/0004-6361/200913273, S2CID 7164596, A71.
  5. ^ a b "del03 Tau". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-08-07.{{cite web}}: CS1 maint: postscript (link)
  6. ^ Falkner, David E. (2011), The Mythology of the Night Sky: An Amateur Astronomer's Guide to the Ancient Greek and Roman Legends, The Patrick Moore Practical Astronomy Series, Springer Science & Business Media, p. 36, ISBN 978-1461401377.
  7. ^ Bagnall, Philip M. (2012), The Star Atlas Companion: What you need to know about the Constellations, Springer Praxis Books, Springer Science & Business Media, p. 422, ISBN 978-1461408307
  8. ^ "Family of the Hyades", Theoi Greek Mythology, retrieved 2017-08-08.
  9. ^ (in Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
  10. ^ (in Chinese) 香港太空館 - 研究資源 - 亮星中英對照表 Archived 2008-10-25 at the Wayback Machine, Hong Kong Space Museum. Accessed on line November 23, 2010.
  11. ^ Kholopov, P. N.; et al. (February 1981), "65th Name-List of Variable Stars", Information Bulletin on Variable Stars, 1921: 1, Bibcode:1981IBVS.1921....1K.
  12. ^ Adelman, S. J. (June 1997), "On the possible variability of metallic-line and Mercury-Manganese stars", Astronomy & Astrophysics Supplement Series, 123 (3): 445–447, Bibcode:1997A&AS..123..445A, doi:10.1051/aas:1997167.
  13. ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122: 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.