Castor (star)
From Tardis Wiki, the free Doctor Who reference
Castor was a star visible from Earth in the constellation of Gemini with the twin star Pollux. Once Ian Chesterton showed it to Vicki Pallister. (PROSE: Byzantium!)
Behind the scenes
In the real world it was named after the mythological figures of Castor and Pollux. It's also the same star as Alpha Geminorum.
