139 Tauri


139 Tauri
Observation data
Epoch J2000      Equinox J2000
Constellation Taurus
Right ascension 05h 57m 59.65632s[1]
Declination +25° 57′ 14.0799″[1]
Apparent magnitude (V) 4.81[2]
Spectral type B1 Ib[3][4] or B0.5 II[5]
B−V color index −0.088±0.003[2]
Radial velocity (Rv)+8.0±4.2[6] km/s
Proper motion (μ) RA: −2.06[1] mas/yr
Dec.: −1.95[1] mas/yr
Parallax (π)2.10 ± 0.19[1] mas
Distance1,600 ± 100 ly
(480 ± 40 pc)
Absolute magnitude (MV)−4.4[7]
Mass10.1±1.0[3] M
Radius20.7[8] R
Luminosity81,000[8] L
Surface gravity (log g)3.559±0.059[5] cgs
Temperature24,660±1,620[4] K
Rotational velocity (v sin i)140[9] km/s
Age22.5±2.6[3] Myr
Other designations
139 Tau, BD+25° 1052, HD 40111, HIP 28237, HR 2084, SAO 77775[10]
Database references

139 Tauri is a single,[11] blue-white hued star in the zodiac constellation of Taurus. It is faintly visible to the naked eye with an apparent visual magnitude of 4.81.[2] The distance to this star, as determined from an annual parallax shift of 2.10±0.19 mas,[1] is roughly 1,600 light years. Because this star is located near the ecliptic, it is subject to occultations by the Moon. One such event was observed April 28, 1990.[12]

This is a massive B-type lower-luminosity supergiant or bright giant star with a stellar classification of B1 Ib[3][4] or B0.5 II,[5] respectively. It is around 22.5[3] million years old with a high rate of spin, showing a projected rotational velocity of 140 km/s.[9] J. D. Rosendhal (1973) identified weak emission features associated with an asymmetric H-alpha absorption line, providing evidence of mass loss.[13] The star has about 10[3] times the mass of the Sun and around 20[8] times the Sun's radius. It is radiating over 80,000[8] times the Sun's luminosity from its photosphere at an effective temperature of around 24,660 K.[4] Stars such as this with 10 or more solar masses are expected to end their life by exploding as a Type II supernova.[14]


  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 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.
  3. ^ a b c d e f Tetzlaff, N.; et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.
  4. ^ a b c d Zorec, J.; et al. (2009), "Fundamental parameters of B supergiants from the BCD system. I. Calibration of the (λ1, D) parameters into Teff", Astronomy and Astrophysics, 501 (1): 297–320, arXiv:0903.5134, Bibcode:2009A&A...501..297Z, doi:10.1051/0004-6361/200811147, S2CID 14969137
  5. ^ a b c Huang, W.; Gies, D. R. (August 2008), "Stellar Rotation in Field and Cluster B Stars", The Astrophysical Journal, 683 (2): 1045–1051, arXiv:0805.2133, Bibcode:2008ApJ...683.1045H, doi:10.1086/590106, S2CID 18926523.
  6. ^ De Bruijne, J. H. J.; Eilers, A.-C. (2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: A61, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347.
  7. ^ Wegner, W (2003). "The total-to-selective extinction ratio determined from near IR photometry of OB stars". Astronomische Nachrichten. 324 (3): 219–237. Bibcode:2003AN....324..219W. doi:10.1002/asna.200310081.
  8. ^ a b c d Lamers, H. J. G. L. M (1981). "Mass loss from O and B stars". The Astrophysical Journal. 245: 593. Bibcode:1981ApJ...245..593L. doi:10.1086/158835.
  9. ^ a b Simón-Díaz, S.; Herrero, A. (2014), "The IACOB project. I. Rotational velocities in northern Galactic O- and early B-type stars revisited. The impact of other sources of line-broadening", Astronomy & Astrophysics, 562: A135, arXiv:1311.3360, Bibcode:2014A&A...562A.135S, doi:10.1051/0004-6361/201322758, S2CID 119278062.
  10. ^ "139 Tau". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-03-30.
  11. ^ 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.
  12. ^ Meyer, C.; et al. (1995), "Observations of lunar occultations at Observatoire de la Cote d'Azur", Astronomy and Astrophysics Supplement, 110: 107, Bibcode:1995A&AS..110..107M.
  13. ^ Rosendhal, J. D. (December 1973), "A survey of H-alpha emission in early-type high-luminosity stars", Astrophysical Journal, 186: 909, Bibcode:1973ApJ...186..909R, doi:10.1086/152555.
  14. ^ Reed, B. Cameron (June 28, 2005), "New Estimates of the Solar-Neighborhood Massive-Stars Birthrate and the Galactic Supernova Rate", The Astronomical Journal, 130 (4): 1652–1657, arXiv:astro-ph/0506708, Bibcode:2005AJ....130.1652R, doi:10.1086/444474, S2CID 119515135.