Castor and Pollux

For the stars, see Castor (star) and Pollux (star), and for the sculptural group in the Prado Museum see Castor and Pollux (Prado). In Greek mythology the Dioskouroi (Διόσκουροι), Kastor and Polydeuces (Κάστωρ και Πολυδεύκης), in Roman mythology  the Gemini (Latin, "twins") or Castores, Castor and Pollux are the twin sons of Leda and the brothers of Helen of Troy and Clytemnestra. According to Liddell and Scott's Lexicon, kastor is Greek for "he who excels", and poludeukeis means "very sweet".
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See Saint Elmo's fire, under Saint.
  

(Acts 28:11) the twin sons of Jupiter and Leda, were regarded as the tutelary divinities of sailors; hence their image was often used as a figure-head for ships. They appeared in heaven as the constellation Gemini . In art they were sometimes represented simply as stars hovering over a ship.