Changes

Rigel is actually a binary star system, although only the primary star can be seen from [[Earth]] by the unaided eye.  It was first discovered as such in 1831 by F. G. W. Struve who was able to resolve the companion star with his telescope, despite the overwhelming brightness of its primary.

Rigel is actually a binary star system, although only the primary star can be seen from [[Earth]] by the unaided eye.  It was first discovered as such in 1831 by F. G. W. Struve who was able to resolve the companion star with his telescope, despite the overwhelming brightness of its primary.

As the Rigel system is far beyond the distance a star can be precisely measured using [[parallax]] measurements, its distance can only be estimated.  The star is believed to be between 700 and 900 light-years distant. The [[Hipparcos]] probe has estimated the distance to be some 860 light years distant.<ref name="illinois">{{cite web|url=http://www.astro.illinois.edu/~jkaler/sow/rigel.html|title=Rigel|accessdate=2019-01-25|archiveurl=https://web.archive.org/web/20090724035044/http://www.astro.illinois.edu/~jkaler/sow/rigel.html|archivedate=2009-07-24}}</ref>

As the Rigel system is far beyond the distance a star can be precisely measured using [[parallax]] measurements, its distance can only be estimated.  The star is believed to be between 700 and 900 light-years distant.<ref name=britannica/><ref name=astropixels/> The [[Hipparcos]] probe has estimated the distance to be some 860 light years distant.<ref name="illinois">{{cite web|url=http://www.astro.illinois.edu/~jkaler/sow/rigel.html|title=Rigel|accessdate=2019-01-25|archiveurl=https://web.archive.org/web/20090724035044/http://www.astro.illinois.edu/~jkaler/sow/rigel.html|archivedate=2009-07-24}}</ref>

The primary star is so bright that it illuminates the dust clouds in nearby nebula, the most famous being the [[Witch head nebula]] 40&nbsp;[[AU]] away.<ref>{{cite web|url=https://www.space.com/22872-rigel.html|title=Rigel: Orion's Brightest Star|accessdate=2019-01-25}}</ref>

The primary star is so bright that it illuminates the dust clouds in nearby nebula, the most famous being the [[Witch head nebula]] 40&nbsp;[[AU]] away.<ref>{{cite web|url=https://www.space.com/22872-rigel.html|title=Rigel: Orion's Brightest Star|accessdate=2019-01-25}}</ref>