Gemini Docking Mechanism

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The Gemini spacecraft used a dedicated docking system to connect with the Agena target vehicle or Augmented Target Docking Adapter. It was the first American spacecraft able to dock with another in space.

Gemini's half of the system had three latch receptacles around the front (the rendezvous and recovery section). The Agena target carried a truncated cone that lined up with those latches to guide Gemini's nose into place. A notch in the cone matched an indexing bar on Gemini to align the two ships in roll. Unlike the later Apollo docking mechanism, Gemini's system did not provide an interior passage between the ships; it simply locked them together and carried an electronic link to allow the Gemini crew to control Agena from their cockpit.