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A crowded six-star system about 50 light-years from Earth. It forms one of the “heads” of the twins of Gemini, and is Gemini’s second-brightest star, after nearby Pollux.

Radio Programs

Castor A miniature “star cluster” January 7, 2017

Gemini Rising The impressive celestial twins December 26, 2014

Castor Rare sextuplets among the stars February 28, 2014

Castor Three sets of stellar twins January 14, 2013