Gemini
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Original Series
The Gemini also appears in the Original Series as the ship where Cassiopeia is rescued in "Saga of a Star World."
Re-imagined Series
The Gemini is an FTL-capable freighter in the Fleet which Sharon "Boomer" Valerii escorts to Laura Roslin's convoy of stranded ships during the Cylon attack.
According to Lee Adama, the Gemini is a tylium refinery ship, and its presence is well appreciated since many of the ships in the convoy require fuel (Miniseries).
Notes
Interestingly, to the Colonials, "Gemini" is the ancient word for Gemenon. Why the ship's owners chose to use this ancient term (rather than the contemporary) is unclear.