BI 253

Last updated
BI 253
BI 253 Tarantula.jpg
NW portion of the Tarantula Nebula, with BI 253 towards the top right
Credit: Hubble Legacy Archive
Observation data
Epoch J2000       Equinox J2000
Constellation Dorado
Right ascension 05h 37m 34.461s [1]
Declination −69° 01′ 10.20″ [1]
Apparent magnitude  (V)13.76 [2]
Characteristics
Evolutionary stage Main sequence [3]
Spectral type O2V-III(n)((f*)) [3]
U−B color index −1.02 [4]
B−V color index −0.13 [4]
Astrometry
Proper motion (μ)RA: 2.3 [1]   mas/yr
Dec.: 3.1 [1]   mas/yr
Distance 164,000  ly
(50,000 [5]   pc)
Absolute magnitude  (MV)−5.7 [3]
Details [6]
Mass 97.6  M☉
Radius 13.9  R☉
Luminosity 1,175,000  L☉
Surface gravity (log g)4.02  cgs
Temperature 54,000  K
Rotational velocity (v sin i)185 km/s
Age 0.4+0.8
−0.4  Myr
Other designations
BI 253, VFTS  72, 2MASS  J05373446-6901102, IRSF  J05373446-6901102
Database references
SIMBAD data

BI 253 is an O2V star in the Large Magellanic Cloud and is a primary standard of the O2 type. It is one of the hottest main-sequence stars known and one of the most-massive and most-luminous stars known.

Contents

Discovery

Tarantula Nebula with BI 253 towards top right (TRAPPIST/E. Jehin/ESO) Tarantula Nebula TRAPPIST.jpg
Tarantula Nebula with BI 253 towards top right
(TRAPPIST/E. Jehin/ESO)

BI 253 was first catalogued in 1975 as the 253rd of 272 likely O and early B stars in the Large Magellanic Cloud. [4] In 1995, the spectral type was analysed to be O3 V, the earliest type defined at that time. [7]

When the classification of the earliest type O stars was refined in 2002, the complete lack of neutral helium or doubly ionised nitrogen lines in the spectrum led to BI 253 being placed in a new O2 V class. It was given a ((f*)) qualifier because of the very weak emission lines of helium and nitrogen. [8] The most recent published data gives a spectral type of O2V-III(n)((f*)), although it is unclear whether this is due to higher quality spectra or an actual change in the spectrum. [3] [9]

BI 253 has been identified as a runaway star because of its relatively isolated position outside the main star-forming areas of 30 Doradus, [10] [11] and because of its high space velocity. It was potentially ejected from the R136 cluster about a million years ago. [12]

Properties

BI 253 is one of the hottest, most massive, and most luminous known main sequence stars. [13] The temperature is around 54,000 K, the luminosity over a million L☉, and the mass of nearly 100 M☉, although its radius is less than 14 R☉. The rotation rate of around 185 km/s is high, but this is common in the youngest and hottest stars, either due to spin-up during stellar formation or merger of a close binary system.

Evolution

BI 253 is still burning hydrogen in its core, but shows enrichment of nitrogen and helium at the surface due to strong rotational and convectional mixing and because of its strong stellar wind. It is very close to the expected ZAMS position for an 85 M☉ star. It is expected that stars more massive than BI 253 would show a giant or supergiant luminosity class even on the main sequence. [13]

Related Research Articles

<span class="mw-page-title-main">R136</span> Super star cluster in the constellation Dorado, in the Large Magellanic Cloud

R136 is the central concentration of stars in the NGC 2070 star cluster, which lies at the centre of the Tarantula Nebula in the Large Magellanic Cloud. When originally named it was an unresolved stellar object but is now known to include 72 class O and Wolf–Rayet stars within 5 parsecs of the centre of the cluster. The extreme number and concentration of young massive stars in this part of the LMC qualifies it as a starburst region.

<span class="mw-page-title-main">NGC 2060</span> Star cluster in the constellation Dorado

NGC 2060 is a star cluster within the Tarantula Nebula in the Large Magellanic Cloud, very close to the larger NGC 2070 cluster containing R136. It was discovered by John Herschel in 1836. It is a loose cluster approximately 10 million years old, within one of the Tarantula Nebula's superbubbles formed by the combined stellar winds of the cluster or by old supernovae.

<span class="mw-page-title-main">R136b</span> Star in the constellation Dorado

R136b is a Wolf–Rayet star in the R136 cluster in the Large Magellanic Cloud. It is one of the most massive and most luminous stars known. It is found in the dense R136 open cluster at the centre of NGC 2070 in the Tarantula Nebula.

<span class="mw-page-title-main">HD 269810</span> Star in the constellation Dorado

HD 269810 is a blue giant star in the Large Magellanic Cloud. It is one of the most massive and most luminous stars known, and one of only a handful of stars with the spectral type O2.

<span class="mw-page-title-main">R136a1</span> Wolf–Rayet star with one of the highest mass and luminosity of any known star

R136a1 is one of the most massive and luminous stars known, at 196 M☉ and nearly 4.7 million L☉, and is also one of the hottest, at around 46,000 K. It is a Wolf–Rayet star at the center of R136, the central concentration of stars of the large NGC 2070 open cluster in the Tarantula Nebula in the Large Magellanic Cloud. The cluster can be seen in the far southern celestial hemisphere with binoculars or a small telescope, at magnitude 7.25. R136a1 itself is 100 times fainter than the cluster and can only be resolved using speckle interferometry.

<span class="mw-page-title-main">Melnick 42</span> Massive blue supergiant star in the constellation Dorado

Melnick 42 is a massive blue supergiant star in the Tarantula Nebula in the Large Magellanic Cloud located in the constellation Dorado. Although it is only 21 times the size of the sun, its high temperature of 47,300 K makes it one of the most luminous stars of the Tarantula Nebula at 3,600,000 L☉. It is less than two parsecs from the centre of the R136 cluster, although that is well outside the central core.

<span class="mw-page-title-main">VFTS 682</span> Wolf Rayet star in the constellation Dorado

VFTS 682 is a Wolf–Rayet star in the Large Magellanic Cloud. It is located over 29 parsecs (95 ly) north-east of the massive cluster R136 in the Tarantula Nebula. It is 138 times the mass of the sun and 3.2 million times more luminous which makes it one of the most massive and most luminous stars known.

<span class="mw-page-title-main">R136a2</span> Star in the constellation Dorado

R136a2 is a Wolf-Rayet star residing near the center of the R136, the central concentration of stars of the large NGC 2070 open cluster in the Tarantula Nebula, a massive H II region in the Large Magellanic Cloud which is a nearby satellite galaxy of the Milky Way. It has one of the highest confirmed masses and luminosities of any known star, at about 151 M☉ and 3.5 million L☉ respectively.

<span class="mw-page-title-main">R136c</span> Star in the constellation Dorado

R136c is a star located in R136, a tight knot of stars at the centre of NGC 2070, an open cluster weighing 450,000 solar masses and containing 10,000 stars. At 142 M☉ and 3.8 million L☉, it is the one of the most massive stars known and one of the most luminous, along with being one of the hottest, at over 40,000 K. It was first resolved and named by Feitzinger in 1980, along with R136a and R136b.

HD 38282 is a massive spectroscopic binary star in the Tarantula Nebula, consisting of two hydrogen-rich Wolf-Rayet stars.

<span class="mw-page-title-main">R136a3</span> Star in the constellation Dorado

R136a3 is a Wolf–Rayet star in R136, a massive star cluster located in Dorado. It is located near R136a1, the most massive and luminous star known. R136a3 is itself one of the most massive and most luminous stars known at about 179 times more massive and 5 million times more luminous than the Sun.

<span class="mw-page-title-main">Melnick 34</span> Binary star in the Large Magellanic cloud

Melnick 34, also called BAT99-116, is a binary Wolf–Rayet star near R136 in the 30 Doradus complex in the Large Magellanic Cloud. Both components are amongst the most massive and most luminous stars known, and the system is the most massive known binary system.

BAT99-98 is a star in the Large Magellanic Cloud. It is located near the R136 cluster in the 30 Doradus nebula. At 226 M☉ and 5,000,000 L☉ it is one of the most massive and luminous stars known.

R99 is a star in the Large Magellanic Cloud in the constellation Dorado. It is classified as a possible luminous blue variable and is one of the most luminous stars known.

<span class="mw-page-title-main">VFTS 352</span> Contact binary star system in the constellation Dorado

VFTS 352 is a contact binary star system 160,000 light-years (49,000 pc) away in the Tarantula Nebula, which is part of the Large Magellanic Cloud. It is the most massive and earliest spectral type overcontact system known.

<span class="mw-page-title-main">R145</span> Binary star in the constellation Dorado

R145 is a spectroscopic binary star in the Tarantula Nebula in the Large Magellanic Cloud located in the constellation Dorado. Both components are amongst the most luminous known.

<span class="mw-page-title-main">VFTS 243</span>

VFTS 243 is an O7V type main sequence star that orbits a stellar mass black hole. The black hole is around nine times the mass of the Sun, with the blue star being 25 times the mass of the Sun making the star 200,000 times larger than the black hole. VFTS 243 is located in the Large Magellanic Cloud inside NGC 2070 around 160,000 light years from Earth. The binary has an orbital period of 10.4 days.

References

  1. 1 2 3 4 Zacharias, N.; Urban, S. E.; Zacharias, M. I.; Wycoff, G. L.; Hall, D. M.; Germain, M. E.; Holdenried, E. R.; Winter, L. (2003). "VizieR Online Data Catalog: The Second U.S. Naval Observatory CCD Astrograph Catalog (UCAC2)". CDS/ADC Collection of Electronic Catalogues. 1289. Bibcode:2003yCat.1289....0Z.
  2. ↑ Rivero González, J. G.; Puls, J.; Najarro, F.; Brott, I. (2012). "Nitrogen line spectroscopy of O-stars. II. Surface nitrogen abundances for O-stars in the Large Magellanic Cloud". Astronomy & Astrophysics. 537: A79. arXiv: 1110.5148 . Bibcode:2012A&A...537A..79R. doi:10.1051/0004-6361/201117790. S2CID   119110554.
  3. 1 2 3 4 Bestenlehner, J. M.; Gräfener, G.; Vink, J. S.; Najarro, F.; De Koter, A.; Sana, H.; Evans, C. J.; Crowther, P. A.; Hénault-Brunet, V.; Herrero, A.; Langer, N.; Schneider, F. R. N.; Simón-Díaz, S.; Taylor, W. D.; Walborn, N. R. (2014). "The VLT-FLAMES Tarantula Survey. XVII. Physical and wind properties of massive stars at the top of the main sequence". Astronomy & Astrophysics. 570: A38. arXiv: 1407.1837 . Bibcode:2014A&A...570A..38B. doi:10.1051/0004-6361/201423643. S2CID   118606369.
  4. 1 2 3 Brunet, J. P.; Imbert, M.; Martin, N.; Mianes, P.; Prévot, L.; Rebeirot, E.; Rousseau, J. (1975). "Studies of the LMC stellar content. I. A catalogue of 272 new O-B2 stars". Astronomy and Astrophysics. 21: 109. Bibcode:1975A&AS...21..109B.
  5. ↑ Evans, C. J.; Taylor, W. D.; Hénault-Brunet, V.; Sana, H.; De Koter, A.; Simón-Díaz, S.; Carraro, G.; Bagnoli, T.; Bastian, N.; Bestenlehner, J. M.; Bonanos, A. Z.; Bressert, E.; Brott, I.; Campbell, M. A.; Cantiello, M.; Clark, J. S.; Costa, E.; Crowther, P. A.; De Mink, S. E.; Doran, E.; Dufton, P. L.; Dunstall, P. R.; Friedrich, K.; Garcia, M.; Gieles, M.; Gräfener, G.; Herrero, A.; Howarth, I. D.; Izzard, R. G.; et al. (2011). "The VLT-FLAMES Tarantula Survey. I. Introduction and observational overview". Astronomy & Astrophysics. 530: A108. arXiv: 1103.5386 . Bibcode:2011A&A...530A.108E. doi:10.1051/0004-6361/201116782. S2CID   54501763.
  6. ↑ Schneider, F. R. N.; Sana, H.; Evans, C. J.; Bestenlehner, J. M.; Castro, N.; Fossati, L.; Gräfener, G.; Langer, N.; Ramírez-Agudelo, O. H.; Sabín-Sanjulián, C.; Simón-Díaz, S.; Tramper, F.; Crowther, P. A.; De Koter, A.; De Mink, S. E.; Dufton, P. L.; Garcia, M.; Gieles, M.; Hénault-Brunet, V.; Herrero, A.; Izzard, R. G.; Kalari, V.; Lennon, D. J.; Maíz Apellániz, J.; Markova, N.; Najarro, F.; Podsiadlowski, Ph.; Puls, J.; Taylor, W. D.; et al. (2018). "An excess of massive stars in the local 30 Doradus starburst". Science. 359 (6371): 69–71. arXiv: 1801.03107 . Bibcode:2018Sci...359...69S. doi:10.1126/science.aan0106. PMID   29302009. S2CID   206658504.
  7. ↑ Massey, Philip; Lang, Cornelia C.; Degioia-Eastwood, Kathleen; Garmany, Catharine D. (1995). "Massive stars in the field and associations of the magellanic clouds: The upper mass limit, the initial mass function, and a critical test of main-sequence stellar evolutionary theory". Astrophysical Journal. 438: 188. Bibcode:1995ApJ...438..188M. doi:10.1086/175064.
  8. ↑ Walborn, Nolan R.; Howarth, Ian D.; Lennon, Daniel J.; Massey, Philip; Oey, M. S.; Moffat, Anthony F. J.; Skalkowski, Gwen; Morrell, Nidia I.; Drissen, Laurent; Parker, Joel Wm. (2002). "A New Spectral Classification System for the Earliest O Stars: Definition of Type O2". The Astronomical Journal. 123 (5): 2754. Bibcode:2002AJ....123.2754W. doi: 10.1086/339831 .
  9. ↑ Walborn, N. R.; Sana, H.; Simón-Díaz, S.; Maíz Apellániz, J.; Taylor, W. D.; Evans, C. J.; Markova, N.; Lennon, D. J.; De Koter, A. (2014). "The VLT-FLAMES Tarantula Survey. XIV. The O-type stellar content of 30 Doradus". Astronomy & Astrophysics. 564: A40. arXiv: 1402.6969 . Bibcode:2014A&A...564A..40W. doi:10.1051/0004-6361/201323082. S2CID   119302111.
  10. ↑ Gvaramadze, V. V.; Kroupa, P.; Pflamm-Altenburg, J. (2010). "Massive runaway stars in the Large Magellanic Cloud". Astronomy and Astrophysics. 519: A33. arXiv: 1006.0225 . Bibcode:2010A&A...519A..33G. doi:10.1051/0004-6361/201014871. S2CID   118579026.
  11. ↑ Evans, C. J.; Walborn, N. R.; Crowther, P. A.; Hénault-Brunet, V.; Massa, D.; Taylor, W. D.; Howarth, I. D.; Sana, H.; Lennon, D. J.; Van Loon, J. Th. (2010). "A Massive Runaway Star from 30 Doradus". The Astrophysical Journal Letters. 715 (2): L74. arXiv: 1004.5402 . Bibcode:2010ApJ...715L..74E. doi:10.1088/2041-8205/715/2/L74. S2CID   118498849.
  12. ↑ Lennon, D. J.; Evans, C. J.; Van Der Marel, R. P.; Anderson, J.; Platais, I.; Herrero, A.; De Mink, S. E.; Sana, H.; Sabbi, E.; Bedin, L. R.; Crowther, P. A.; Langer, N.; Ramos Lerate, M.; Del Pino, A.; Renzo, M.; Simón-Díaz, S.; Schneider, F. R. N. (2018). "Gaia DR2 reveals a very massive runaway star ejected from R136". Astronomy and Astrophysics. 619: A78. arXiv: 1805.08277 . Bibcode:2018A&A...619A..78L. doi:10.1051/0004-6361/201833465. S2CID   59058322.
  13. 1 2 Doran, Emile I.; Crowther, Paul A. (2011). "A VLT/UVES spectroscopy study of O2 stars in the LMC". Société Royale des Sciences de Liège. 80: 129. Bibcode:2011BSRSL..80..129D.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.