The Gemini 8 crew did the first docking ever in space at 6 hours, 33 minutes into the mission. All went well for about 27 minutes,
according to the Gemini 8 mission report
, until the crew noticed the docked spacecraft were moving unexpectedly. When the crew realized that it would take too much fuel to stabilize the spacecraft, they undocked. That's when they knew something was wrong with the spacecraft itself, as it eventually rotated as fast as almost one complete revolution per second. Armstrong quickly activated the re-entry control system, saving the crew from blackout and big trouble. (It turned out the spacecraft had a stuck-open thruster.) But activating the re-entry system forced them to land just over 10.5 hours after launch.
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