Celestial Objects
Castor
Multiple Star Systems
Citation Formats
General Reference
APA Style
BibTeX
Castor is the second-brightest object in the constellation Gemini, carrying the Bayer designation Alpha Geminorum despite being about half a magnitude fainter than Beta Geminorum, known as Pollux. It appears as a single star to the naked eye but is actually a sextuple star system made up of three separate binary pairs, with an apparent visual magnitude of 1.58 making it one of the brightest stars in the sky.
Reader Challenges (0 open reader challenges)
No disputes yet. Spotted an error or a better source? Open the first one.
Sign in to dispute this or suggest a correction.
View At A Past Year
The atlas records no dated fact of its own for this entry, so there is no other year to choose.