Rigel A

I chose this star because it is the brightest star in the constellation Orion and it is the 7th brightest star in the sky. It, too, is is in a multistar system (Rigel), and it is a blue-white supergiant that is 21 times MORE massive than our sun and shines with about 120,000 times its luminosity. It is a young star of only 10 million years old, and since it is so large, it is expected to become a supernova at the end of its life.

Star: Rigel A

Chemical makeup: composed of helium at core

Location in space: Right ascension- 5 hr 14 min 32.3 sec
Declination- -8 degrees 12' 5.9"
733 light years from Sun

Spectrum analysis of most abundant chemical (helium): 

https://en.wikipedia.org/wiki/Helium

Stellar classification: B8Ia blue-white supergiant
 
http://thecasswiki.net/index.php?title=Rigel  

Sources: 

100,000 Stars. (n.d.). Retrieved September 26, 2015, from http://stars.chromeexperiments.com/

Rigel. (n.d.). Retrieved September 27, 2015, from https://en.wikipedia.org/wiki/Rigel#cite_note-aaa474_2_653-2 

Rigel. (n.d.). Retrieved September 27, 2015, from http://www.stellar-database.com/Scripts/search_star.exe?Name=rigel 
What Are The Most Famous Stars? (2015, February 11). Retrieved September 27, 2015, from http://www.universetoday.com/45775/famous-stars/