Star in the constellation Tucana
Epsilon Tucanae (ε Tuc, ε Tucanae) is a solitary[ 9] star in the southernconstellation ofTucana . With anapparent visual magnitude of +4.50,[ 2] parallax shift of 8.74 mas as seen from Earth, it is located around 373 light years from theSun .
Levenhagen and Leister (2008)classified this star as B8 V,[ 3] B-type main sequence star . However, Hiltner, Garrison, and Schild (1969) listed it with a classification of B9 IV,[ 4] evolved subgiant star . It is a rapidly rotatingBe star that is an estimated 78% of the way through itsmain sequence lifetime.[ 10] projected rotational velocity is 300 km/s,[ 3] oblate shape with anequatorial bulge that is an estimated 36% larger than the polar radius.[ 11] magnetic field with a strength of± 24 G [ 12]
It is the last star in theHipparcos catalogue , HIP 118322, from theHipparcos (1989–1993) astrometry satellite.
^a b c d e 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 . ^a b c d Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars",Communications of the Lunar and Planetary Laboratory ,4 (99): 99,Bibcode :1966CoLPL...4...99J . ^a b c d e f g h i Levenhagen, R. S.; Leister, N. V. (2006), "Spectroscopic Analysis of Southern B and Be Stars",Monthly Notices of the Royal Astronomical Society 371 (1):252– 62,arXiv :astro-ph/0606149 Bibcode :2006MNRAS.371..252L ,doi :10.1111/j.1365-2966.2006.10655.x S2CID 16492030 . ^a b Hiltner, W. A.; et al. (July 1969), "MK Spectral Types for Bright Southern OB Stars",Astrophysical Journal ,157 : 313,Bibcode :1969ApJ...157..313H ,doi :10.1086/150069 ^ Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system",Astronomy Letters ,32 (11):759– 771,arXiv :1606.08053 Bibcode :2006AstL...32..759G ,doi :10.1134/S1063773706110065 ,S2CID 119231169 . ^ 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 ,S2CID 119257644 . ^ Barraza, L. F.; Gomes, R. L.; Messias, Y. S.; Leão, I. C.; Almeida, L. A.; Janot-Pacheco, E.; Brito, A. C.; Brito, F. A. C.; Santana, J. V.; Gonçalves, N. S.; Das Chagas, M. L.; Teixeira, M. A.; De Medeiros, J. R.; Canto Martins, B. L. (2022)."Rotation Signature of TESS B-type Stars. A Comprehensive Analysis" .The Astrophysical Journal .924 (2): 117.arXiv :2202.01022 Bibcode :2022ApJ...924..117B .doi :10.3847/1538-4357/ac3335 S2CID 246030494 . ^ "eps Tuc -- Be Star" ,SIMBAD Astronomical Database ,Centre de Données astronomiques de Strasbourg , retrieved2017-04-22 .^ 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 . ^ Zorec, J.; et al. (October 2005), "On the evolutionary status of Be stars. I. Field Be stars near the Sun",Astronomy and Astrophysics ,441 (1):235– 248,arXiv :astro-ph/0509119 Bibcode :2005A&A...441..235Z ,doi :10.1051/0004-6361:20053051 ,S2CID 17592657 . ^ Belle, G. T. (2012), "Interferometric observations of rapidly rotating stars",The Astronomy and Astrophysics Review ,20 (1): 51,arXiv :1204.2572 Bibcode :2012A&ARv..20...51V ,doi :10.1007/s00159-012-0051-2 ,S2CID 119273474 . ^ Hubrig, S.; et al. (July 2009), "Magnetic survey of emission line B-type stars with FORS 1 at the VLT",Astronomische Nachrichten ,330 (7): 708,arXiv :0907.0882 Bibcode :2009AN....330..708H ,doi :10.1002/asna.200911236 ,S2CID 13620067 .
