View source for Astronomy:WR 102c

{{Starbox begin
| name=WR 102c
}}
{{Starbox image
| image       = [[File:Quintuplet cluster region (1002.3379).jpg|280px]]
| caption     = Region around the Quintuplet Cluster.  Full size image is annotated to show WR 102c.
| credit      = NASA/ESA, Hubble
}}
{{Starbox observe
| epoch=J2000
| dec={{DEC|+28|4905.9}}<ref name=survey/>
| appmag_v=
| constell=[[Astronomy:Sagittarius (constellation)|Sagittarius]]
}}
{{Starbox character
| class=WN6<ref name=steinke>{{Cite journal|title=Analysis of the WN star WR 102c, its WR nebula, and the associated cluster of massive stars in the Sickle Nebula|journal=Astronomy & Astrophysics|volume=588|issue=9|pages=A9|arxiv=1601.03395|last1=Steinke|first1=M.|last2=Oskinova|first2=L. M.|last3=Hamann|first3=W.-R.|last4=Sander|first4=A.|last5=Liermann|first5=A.|last6=Todt|first6=H.|year=2016|doi=10.1051/0004-6361/201527692|bibcode = 2016A&A...588A...9S |s2cid=118469961 }}</ref>
| appmag_1_passband=K
| appmag_1=11.6<ref name=survey/>
| variable=
}}
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{{Starbox detail
| source=<ref name=steinke/>
| mass=
| radius=
| luminosity=320,000-500,000
| temperature=65,000-75,000
| metal=
| rotation=
| age_myr=4 - 6
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{{Starbox catalog
| names=WR&nbsp;102c, qF&nbsp;353E
}}
{{Starbox reference
| Simbad=WR+102c
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'''WR 102c''' is a [[Astronomy:Wolf–Rayet star|Wolf–Rayet star]] located in the constellation [[Astronomy:Sagittarius (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 [[Astronomy:Sun|Sun]].  An initial study reporting a much higher luminosity mistakenly used photometry from a nearby star.<ref name=lau>{{cite journal|bibcode=2016ApJ...818..117L|arxiv=1512.07639|title=An Apparent Precessing Helical Outflow from a Massive Evolved Star: Evidence for Binary Interaction|volume=1512|issue=2|last1=Lau|first1=Ryan M.|last2=Hankins|first2=Matthew J.|last3=Herter|first3=Terry L.|last4=Morris|first4=Mark R.|last5=Mills|first5=Elisabeth A. C.|last6=Ressler|first6=Michael E.|year=2015|doi=10.3847/0004-637X/818/2/117|journal=The Astrophysical Journal|pages=117|s2cid=118391443 |doi-access=free }}</ref><ref name=barniske>{{cite journal|bibcode=2008A&A...486..971B|arxiv=0807.2476|title=Two extremely luminous WN stars in the Galactic center with circumstellar emission from dust and gas|journal=Astronomy and Astrophysics|volume=486|issue=3|pages=971–984|last1=Barniske|first1=A.|last2=Oskinova|first2=L. M.|last3=Hamann|first3=W.-R.|year=2008|doi=10.1051/0004-6361:200809568|s2cid=8074261 }}</ref>  It would have formed as a {{solar mass|40}} [[Astronomy:O-type main-sequence star|O-type main-sequence star]] a few million years ago and has since spent a period as a [[Astronomy:Red supergiant|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 [[Astronomy:Supernova|supernova]] or collapsing directly into a [[Astronomy:Black hole|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 {{solar mass|1|link=y}} of molecular hydrogen and around {{solar mass|10}} of ionised hydrogen, all expelled from the star.<ref name=barniske/>

There is a suggestion that WR 102c may be a [[Astronomy:Binary star|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.<ref name=lau/>  It is surrounded by a small cluster of stars around {{solar mass|1,000}} in total, separate from the much more massive Quintuplet Cluster.<ref name=steinke/>

==References==
{{reflist}}

{{Stars of Sagittarius}}

[[Category:Sagittarius (constellation)]]
[[Category:Wolf–Rayet stars]]

{{Sourceattribution|WR 102c}}