.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] | |
| Luminosity | 320,000-500,000 L☉ |
| Temperature | 65,000-75,000 K |
| Age | 4 - 6 Myr |
| Other designations | |
WR 102c, qF 353E | |
| Database references | |
| SIMBAD | data |
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.
Features
According to recent estimations, WR 102c is as much as 500,000 times brighter than the 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 collapse within the next few hundred thousand years as it runs out of fuel in its core, producing a type Ib or Ic supernova or collapsing directly into a black hole.
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 1,000 M☉ in total, separate from the much more massive Quintuplet Cluster. [2]
References
- ^ 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". 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. S2CID 11060463.
- ^ 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. S2CID 118469961.
- ^ 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. S2CID 118391443.
- ^ 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. S2CID 8074261.
