memory alpha

Castor, also known as Alpha Geminorum or 66 Geminorum, was a star system in the Beta Quadrant.

Components

Stellar system

It was a sextenary system organized into three binary star systems. The three systems were Alpha Geminorum Aab, Alpha Geminorum Bab, and Alpha Geminorum Cab.

The Alpha Geminorum Aab system consisted of the A-type dwarf star Castor (the proper name for Alpha Geminorum Aa) and the companion red dwarf Alpha Geminorum Ab.

The secondary Alpha Geminorum Bab had the A-type dwarf star Alpha Geminorum Ba and the companion red dwarf Alpha Geminorum Bb.

The red dwarfs Alpha Geminorum Ca and Alpha Geminorum Cb made up the tertiary Alpha Geminorum Cab system.

History

In 2257, during the first Federation-Klingon War, the Castor system was occupied by the Klingons. (DIS: "The War Without, The War Within")

When the Venari Ral laid Omega-47 mines around the core of Federation space in 3196, this system was within the enclosed region. (SA: "300th Night", "Rubincon")

Stellar cartography

The Castor system was visible from Earth in the constellation Gemini. This system was approximately 49 light years from Sol.

In 2154, this system's position was labeled on an United Earth star chart showing the location of Cold Station 12. (ENT: "Cold Station 12")

In 2256, the system's location was labeled on the star chart "Alpha/Beta Quadrant Overview" in the ready room aboard the USS Discovery. (DIS: "Magic to Make the Sanest Man Go Mad")

In 3196, this system's position was labeled on a Federation star chart which was displayed on the main viewscreen of the USS Athena bridge. (SA: "Ko'Zeine")

Later that year, during the Omega-47 crisis, the location of Castor (Alpha Geminorum) was depicted on a star chart on the USS Athena, used to display the Omega-47 mines laid by the Venari Ral. (SA: "300th Night", "Rubincon")

This star system was only mentioned in writing.
Information on this system was derived from the episodes and films, the reference works Star Trek: Star Charts and Stellar Cartography: The Starfleet Reference Library, and real-world sources. The reference works were used extensively in the creation of star charts seen in Star Trek: Discovery, Star Trek: Picard, Star Trek: Strange New Worlds, Star Trek: Prodigy, Star Trek: Lower Decks, and Star Trek: Starfleet Academy. The real-world information added to the article was current as of 2026.

External links