Astronomy:WR 102ea

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Short description: Star in the constellation Sagittarius
WR 102ea
Quintuplet cluster.jpg
Cercle jaune 100%.svg
WR 102ea (circled) in the Quintuplet Cluster
Observation data
Equinox J2000.0]] (ICRS)
Constellation Sagittarius
Right ascension {{{ra}}}
Declination −28° 49′ 36.9″[1]
Characteristics
Evolutionary stage Wolf Rayet
Spectral type WN9h[2]
Apparent magnitude (K) 8.8[3]
Astrometry
Radial velocity (Rv)116[4] km/s
Proper motion (μ) RA: -0.59[1] mas/yr
Dec.: -1.21[1] mas/yr
Distance26k[2] ly
(8k[2] pc)
Details
Mass58[5] M
Radius86[2] R
Luminosity2.5 × 106[2] L
Temperature25,100[2] K
Age~4[5] Myr
Other designations
FMM 241, qF 241, (erroneously QPM-241), Q10, MGM 5-10, LHO 71
Database references
SIMBADdata

WR 102ea is a Wolf–Rayet star in the Sagittarius constellation. It is the third most luminous star in the Quintuplet cluster after WR 102hb. With a luminosity of 2,500,000 times solar, it is also one of the most luminous stars known. Despite the high luminosity it can only be observed at infra-red wavelengths due to the dimming effect of intervening dust on visual light.

It is an evolved massive star which has an emission line spectrum from a strong stellar wind caused by high luminosity and the presence of elements heavier than hydrogen in the photosphere. The spectrum is dominated by ionised helium and nitrogen lines due to convectional and rotational mixing of fusion products to the surface of the star. However it is still in a core hydrogen burning phase and hydrogen lines are also visible in the spectrum, in contrast to WN stars without hydrogen which are older, less massive, and less luminous. Despite being a relatively unevolved star, WR 102ea has lost over half its mass already.[5]

References

  1. 1.0 1.1 1.2 Cite error: Invalid <ref> tag; no text was provided for refs named dong
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Liermann, A.; Hamann, W.-R.; Oskinova, L. M.; Todt, H.; Butler, K. (2010). "The Quintuplet cluster". Astronomy & Astrophysics 524: A82. doi:10.1051/0004-6361/200912612. Bibcode2010A&A...524A..82L. 
  3. Liermann, A.; Hamann, W.-R.; Oskinova, L. M. (2009). "The Quintuplet cluster". Astronomy and Astrophysics 494 (3): 1137. doi:10.1051/0004-6361:200810371. Bibcode2009A&A...494.1137L. 
  4. Liermann, A.; Hamann, W.-R.; Oskinova, L. M. (2009). "The Quintuplet cluster. I. A K-band spectral catalog of stellar sources". Astronomy and Astrophysics 494 (3): 1137. doi:10.1051/0004-6361:200810371. Bibcode2009A&A...494.1137L. 
  5. 5.0 5.1 5.2 Liermann, Adriane; Hamann, Wolf-Rainer; Oskinova, Lidia M.; Todt, Helge (2011). "High-mass stars in the Galactic center Quintuplet cluster". Société Royale des Sciences de Liège 80: 160. Bibcode2011BSRSL..80..160L.