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]
Characteristics
Spectral type B1 Ib[3][4] or B0.5 II[5]
B−V color index −0.088±0.003[2]
Astrometry
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 mas[1]
Distance1,600 ± 100 ly
(480 ± 40 pc)
Absolute magnitude (MV)−4.4[7]
Details
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
SIMBADdata

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 Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b c d e f Cite error: The named reference Tetzlaff2011 was invoked but never defined (see the help page).
  4. ^ a b c d Cite error: The named reference Zorec2009 was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference Huang2008 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference DeBruijne2012 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference wegner was invoked but never defined (see the help page).
  8. ^ a b c d Cite error: The named reference lamers was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference diaz2014 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Meyer1995 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Rosendhal1973 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Reed2005 was invoked but never defined (see the help page).