HD 38282

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HD 38282

Observation data
Epoch J2000      Equinox J2000
Constellation Dorado
Right ascension 05h 38m 53.3867s[1]
Declination −69° 02′ 00.901″[1]
Apparent magnitude (V) 11.11[2]
Evolutionary stage Wolf Rayet
Spectral type WN5-6h + WN6-7h[3]
B−V color index −0.13[2]
Proper motion (μ) RA: 2.00[1] mas/yr
Dec.: 2.60[1] mas/yr
Distance 163,000 ly
(49,970[4] pc)
Absolute magnitude (MV) -7.96[5]
Mass 80-170 + 95-205[3] M
Luminosity 4,500,000 (combined)[5] L
Temperature 47,000[5] K
Age <2[3] Myr
Other designations
Brey 89, BAT99 118, RMC 144, R144, 2MASS J05385338-6902007, HD 38282
Database references

HD 38282 (R144, BAT99-118, Brey 89) is a massive spectroscopic binary star in the Tarantula Nebula (Large Magellanic Cloud), consisting of two hydrogen-rich Wolf-Rayet stars.

R144 is located near the R136 cluster at the center of NGC 2070 and may have been ejected from it after an encounter with another massive binary.[6]

Both components of R144 are detected in the spectrum and both are WNh stars, very hot stars with strong emission lines due to their strong stellar winds. The orbit has not been determined, but is likely to be between two and six months long, possibly more if it is eccentric. The primary, slightly hotter, star is observed to be the less massive of the two.[3]

Each star is amongst the most luminous known, but the exact parameters of each has not been determined. Their combined luminosity is around 4,500,000 L[5] to 10,000,000 L.[3] The masses have not yet been calculated accurately from the orbital parameters, but the stars have been modelled to initially have been around 260 M and 175 M. Depending on their exact age, this has now decreased to between 90 M and 170 M for the primary and 95 M and 205 M for the secondary.[3]


  1. ^ a b c d Hog, E.; Kuzmin, A.; Bastian, U.; Fabricius, C.; Kuimov, K.; Lindegren, L.; Makarov, V. V.; Roeser, S. (1998). "The TYCHO Reference Catalogue". Astronomy and Astrophysics. 335: L65. Bibcode:1998A&A...335L..65H. 
  2. ^ a b Zacharias, N.; Finch, C. T.; Girard, T. M.; Henden, A.; Bartlett, J. L.; Monet, D. G.; Zacharias, M. I. (2012). "VizieR Online Data Catalog: UCAC4 Catalogue (Zacharias+, 2012)". VizieR On-line Data Catalog: I/322A. Originally published in: 2012yCat.1322....0Z; 2013AJ....145...44Z. 1322. Bibcode:2012yCat.1322....0Z. 
  3. ^ a b c d e f Sana, H.; Van Boeckel, T.; Tramper, F.; Ellerbroek, L. E.; De Koter, A.; Kaper, L.; Moffat, A. F. J.; Schnurr, O.; Schneider, F. R. N.; Gies, D. R. (2013). "R144 revealed as a double-lined spectroscopic binary". Monthly Notices of the Royal Astronomical Society: Letters. 432: 26. arXiv:1304.4591free to read. Bibcode:2013MNRAS.432L..26S. doi:10.1093/mnrasl/slt029. 
  4. ^ Pietrzyński, G; D. Graczyk; W. Gieren; I. B. Thompson; B. Pilecki; A. Udalski; I. Soszyński; et al. (7 March 2013). "An eclipsing-binary distance to the Large Magellanic Cloud accurate to two per cent". Nature. 495 (7439): 76–79. arXiv:1303.2063free to read. Bibcode:2013Natur.495...76P. doi:10.1038/nature11878. PMID 23467166. 
  5. ^ a b c d 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: A comprehensive analysis of the WN class". arXiv:1401.5474v1free to read [astro-ph.SR]. 
  6. ^ Oh, Seungkyung; Kroupa, Pavel; Banerjee, Sambaran (2014). "R144: A very massive binary likely ejected from R136 through a binary-binary encounter". Monthly Notices of the Royal Astronomical Society. 437 (4): 4000. arXiv:1311.2934free to read. Bibcode:2014MNRAS.437.4000O. doi:10.1093/mnras/stt2219.