Rigel

Rigel is the lower left-hand star of Orion, i.e., foot of his right leg (if he's facing us). It is a quadruple star system, the brightest of which is Rigel A, a blue-white supergiant and Alpha Cygni variable (ACYG). Rigel B is a spectroscopic binary system, with two main-sequence blue-white B9 stars, the pair about 2200 AU from Rigel A. Rigel C is another similar star, which orbits the Rigel B pair with 63 year period. Rigel lights up some nearby nebulae. Note that the determined characteristics depend upon an accurate measure of the star's distance, and determinations still vary. Characteristics based upon one determination:

• Orion - constellation.
• 05h14m32.27210s - right ascension.
• -08deg12m05.8981s - declination.
• +0.13 - apparent magnitude.
• 860 ly - distance.

Rigel A:

• B8 - spectral type.
• 21 - mass(solar).
• 120,000 - luminosity(solar).
• 79 - radius(solar).
• -0.03 - B-V color index.

Rigel B:

• spectroscopic binary.
• two B9 stars.