Melnick 34

BAT99-116

Photograph of Melnick 34 taken by the Wide Field and Planetary Camera of the Hubble Space Telescope.
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Dorado
Right ascension 5h 38m 44.25s
Declination −69° 06′ 05.8″
Apparent magnitude (V) 13.09[1]
Characteristics
Spectral type WN5h:a[2]
B−V color index +0.25[1]
Astrometry
Distance165,000 ly
Absolute magnitude (MV)-7.9[1]
Details
Mass<190[3] M☉
Radius20[2] R☉
Luminosity4.9×106[3] L☉
Temperature63,000[2] K
Age~1.7[3] Myr
Other designations
BAT99 116, [HSH95] 8, Melnick 34, 2MASS J05384424-6906058, Brey 84
Database references
SIMBADdata

BAT99-116 (commonly called Melnick 34 or Mk34) is a massive luminous Wolf–Rayet star near R136 in the 30 Doradus complex (also known as the Tarantula Nebula) in the Large Magellanic Cloud.[3]

Physical characteristics

Mk34 is a Wolf–Rayet star with surface temperature over 60,000 K .[2][1] It is estimated that at its birth the star was around 190 M☉.[3] It has a powerful stellar wind and despite its young age it has already shed a large fraction of its initial mass. However, due to high x-ray luminosity and some radial velocity variations, it is expected that Mk34 has a hot luminous companion, so estimates of its temperature, luminosity, and mass are highly uncertain.[2]

Evolution

Mk34 is currently burning hydrogen in its core, although it shows strong helium and nitrogen emission due to convection of fusion products from the core to the surface. It is expected that it will evolve quickly to a hydrogen-free Wolf-Rayet star, possibly with a short time as a blue hypergiant and luminous blue variable. It will then shed more and more of its outer layers, ultimately becoming a WO star close to 200,000 K before collapsing, producing a type Ic supernova and leaving behind a black hole.[4]

See also

References

  1. 1 2 3 4 Doran, E. I.; Crowther, P. A.; de Koter, A.; Evans, C. J.; McEvoy, C.; Walborn, N. R.; Bastian, N.; Bestenlehner, J. M.; Grafener, G.; Herrero, A.; Kohler, K.; Maiz Apellaniz, J.; Najarro, F.; Puls, J.; Sana, H.; Schneider, F. R. N.; Taylor, W. D.; van Loon, J. Th.; Vink, J. S. (2013). "The VLT-FLAMES Tarantula Survey - XI. A census of the hot luminous stars and their feedback in 30 Doradus". Astronomy & Astrophysics 558: 134. arXiv:1308.3412. Bibcode:2013A&A...558A.134D. doi:10.1051/0004-6361/201321824.
  2. 1 2 3 4 5 Hainich, R.; Rühling, U.; Todt, H.; Oskinova, L. M.; Liermann, A.; Gräfener, G.; Foellmi, C.; Schnurr, O.; Hamann, W. -R. (2014). "The Wolf-Rayet stars in the Large Magellanic Cloud". Astronomy & Astrophysics 565: A27. arXiv:1401.5474. Bibcode:2014A&A...565A..27H. doi:10.1051/0004-6361/201322696.
  3. 1 2 3 4 5 Crowther, P. A.; Schnurr, O.; Hirschi, R.; Yusof, N.; Parker, R. J.; Goodwin, S. P.; Kassim, H. A. (2010). "The R136 star cluster hosts several stars whose individual masses greatly exceed the accepted 150 M⊙ stellar mass limit". Monthly Notices of the Royal Astronomical Society 408 (2): 731. arXiv:1007.3284. Bibcode:2010MNRAS.408..731C. doi:10.1111/j.1365-2966.2010.17167.x.
  4. ↑ Groh, J. H.; Meynet, G.; Georgy, C.; Ekström, S. (2013). "Fundamental properties of core-collapse supernova and GRB progenitors: Predicting the look of massive stars before death". Astronomy & Astrophysics 558: A131. Bibcode:2013A&A...558A.131G. doi:10.1051/0004-6361/201321906.

Coordinates: 05h 38m 44.25s, −69° 06′ 05.8″

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