Astronauts James Lovell and Buzz Aldrin returned safely to Earth aboard Gemini 12, concluding the ten-crewed-mission Gemini program. Aldrin's spacewalks during the flight solved persistent problems with extravehicular activity, including fatigue and tethering, by using handholds and restraints, techniques that proved crucial for the Apollo lunar missions that would follow within three years.
Gemini 12 was in many ways an unglamorous mission—its rendezvous radar failed, forcing Aldrin to compute rendezvous calculations by hand using a sextant and slide rule during descent to their target Agena vehicle. It worked perfectly, a triumph of old-fashioned math over failed electronics.
Aldrin's real legacy from the flight was solving the 'spacewalking problem' that had bedeviled earlier Gemini astronauts, several of whom had become dangerously exhausted and overheated tumbling helplessly outside their capsules. Aldrin, a trained scuba diver, insisted on underwater training to simulate weightlessness, a practice that became standard NASA procedure for every subsequent spacewalk in history.
Jim Lovell would go on to command the ill-fated but heroically recovered Apollo 13 mission, while Aldrin would famously become the second human to walk on the Moon less than three years later. Gemini 12's quiet, workmanlike success masked how essential it was: without solving the EVA fatigue problem here, the Apollo program's lunar surface moonwalks might have been dangerously improvised rather than methodically rehearsed.
Key people: James Lovell, Buzz Aldrin