WR 102c is a Wolf–Rayet star located in the constellation Sagittarius towards the galactic centre. It is only a few parsecs from the Quintuplet Cluster, within the Sickle Nebula.

WR 102c
Quintuplet cluster region (1002.3379).jpg
Region around the Quintuplet Cluster. Full size image is annotated to show WR 102c.
Credit: NASA/ESA, Hubble
Observation data
Epoch J2000      Equinox J2000
Constellation Sagittarius
Right ascension  17h 46m 11.14s[1]
Declination +28° 4905.9′[1]
Characteristics
Spectral type WN6[2]
Apparent magnitude (K) 11.6[1]
Details[2]
Luminosity320,000-500,000 L
Temperature65,000-75,000 K
Age4 - 6 Myr
Other designations
WR 102c, qF 353E
Database references
SIMBADdata

FeaturesEdit

According to recent estimations, WR 102c is as much as 500,000 times brighter than our Sun. An initial study reporting a much higher luminosity mistakenly used photometry from a nearby star.[3][4] It would have formed as a 40 M O-type main-sequence star a few million years ago and has since spent a period as a red supergiant before losing its outer layers completely. It is now almost hydrogen-free and nearing the end of its life. It will produce a type Ib or Ic supernova within the next few hundred thousand years.

WR 102c is surrounded by a shell of nebulosity which contains dust made even hotter than the star itself by intense radiation. The nebula also includes nearly 1 M of molecular hydrogen and around 10 M of ionised hydrogen, all expelled from the star.[4]

There is a suggestion that WR 102c may be a binary star. A nearby corkscrew-shaped jet of nebulosity could have been expelled during the orbital motion. which would imply a period of 800 - 1,400 days.[3] It is surrounded by a small cluster of stars around 1000 M in total, separate from the much more massive Quintuplet Cluster.[2]

ReferencesEdit

  1. ^ a b c Dong, H.; Wang, Q. D.; Cotera, A.; Stolovy, S.; Morris, M. R.; Mauerhan, J.; Mills, E. A.; Schneider, G.; Calzetti, D.; Lang, C. (2011). "Hubble Space Telescope Paschen α survey of the Galactic Centre: Data reduction and products" (PDF). Monthly Notices of the Royal Astronomical Society. 417: 114–135. arXiv:1105.1703. Bibcode:2011MNRAS.417..114D. doi:10.1111/j.1365-2966.2011.19013.x.
  2. ^ a b c Steinke, M.; Oskinova, L. M.; Hamann, W.-R.; Sander, A.; Liermann, A.; Todt, H. (2016). "Analysis of the WN star WR 102c, its WR nebula, and the associated cluster of massive stars in the Sickle Nebula". Astronomy & Astrophysics. 588 (9): A9. arXiv:1601.03395. Bibcode:2016A&A...588A...9S. doi:10.1051/0004-6361/201527692.
  3. ^ a b Lau, Ryan M.; Hankins, Matthew J.; Herter, Terry L.; Morris, Mark R.; Mills, Elisabeth A. C.; Ressler, Michael E. (2015). "An Apparent Precessing Helical Outflow from a Massive Evolved Star: Evidence for Binary Interaction". The Astrophysical Journal. 1512 (2): 117. arXiv:1512.07639. Bibcode:2016ApJ...818..117L. doi:10.3847/0004-637X/818/2/117.
  4. ^ a b Barniske, A.; Oskinova, L. M.; Hamann, W.-R. (2008). "Two extremely luminous WN stars in the Galactic center with circumstellar emission from dust and gas". Astronomy and Astrophysics. 486 (3): 971–984. arXiv:0807.2476. Bibcode:2008A&A...486..971B. doi:10.1051/0004-6361:200809568.