Neil Armstrong docked with the Agena target vehicle today — the first docking in space — and then had to cut the mission short when Gemini 8 started spinning.

The docking worked. Armstrong flew Gemini 8 to the Agena, an unmanned target vehicle that had launched earlier, and the two spacecraft locked together. First docking in history. Apollo just got cleared for the Moon trip, at least in principle.

Then something went wrong.

After docking, the joined spacecraft started rolling. Mission Control and the crew assumed it was the Agena’s thruster misfiring, so they tried to compensate with Gemini’s thrusters, which made it worse. Eventually the roll accelerated to the point where both men were approaching the limit of conscious action — roughly one revolution per second, serious enough to cause incapacitation.

Armstrong made the decision to undock from the Agena. This is the correct call, but it had a consequence: one of Gemini 8’s own thrusters was stuck open, and once the combined mass of the Agena was removed, Gemini 8 started spinning even faster. The roll rate got above one revolution per second before Armstrong managed to stabilize it by activating the re-entry control thrusters, which was a last resort because using those thrusters meant the mission rules required an immediate abort.

They came down safely. Three days in space instead of the planned three. Dave Scott’s EVA — which had been the main objective after docking — never happened.

Neil Armstrong made the right call under pressure. Not just the undocking decision, but the whole sequence. With a pilot who panicked or hesitated, that spin could have become fatal. He didn’t panic and he didn’t hesitate and he brought both of them home.

I’ve been paying attention to Armstrong for a while now. He’s quieter than most of them. More technical, less theatrical. He came from a research pilot background at Edwards, where they test things at the limits of what’s physically possible, and you develop a very matter-of-fact relationship with emergency.

I have a feeling we’ll hear more from Neil Armstrong. Something about the way he handles himself in a crisis.