WR 102c
.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
[edit]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
[edit]- ^ 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 (1): 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.
