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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

Moon and Twins Some looong trips through the cosmos March 2, 2023

Moon and Gemini A set of “twins” that don’t match February 13, 2022

Moon and Gemini Sextuplets in the night sky February 23, 2021

The Twins A goodly supply of twins January 26, 2019

Castor A miniature “star cluster” January 7, 2017