Gemini Station was a Federation facility active in the 23rd century. In appearance, the station resembled two K-type space stations attached at their bases. In the fourth year (2269-70) of its five-year mission, the USS Enterprise was conducting research into the origin of the universe at Gemini Station. An accident resulted in the formation of quark gluon plasma. Spock, trapped aboard the space station, relied on Chekov's ingenuity as acting science officer to help rescue him. (TOS comic: "Year Four, Issue 5")