A binary star system where the Enterprise was due to meet the USS Potemkin for gravitational studies in 2269, a rendezvous delayed when Janice Lester took command in Kirk's body.
Beta Aurigae is mentioned in Turnabout Intruder, the final episode of the original series. After answering a distress call from Camus II, the Enterprise is expected to continue to the binary system to carry out gravitational studies alongside the starship Potemkin.
Janice Lester, occupying Kirk's body, instead orders a change of course for the Benecia colony, where she intends to abandon the real Kirk, trapped in her own body, at a facility poorly equipped to treat him. Spock points out that Starbase 2 lies on the original route and offers far better medical care.
The needless diversion and the missed rendezvous are among the first things that convince Spock that the captain is not himself.