Jun 05, 2026

One year after Gemini IV astronaut Edward H. White completed NASA’s first spacewalk the agency prepared for a demanding second excursion. Originally scheduled for Gemini VIII, the extravehicular activity (EVA) was reassigned to Gemini IX-A after that mission ended early, with Gene Cernan taking on the task.

On June 5, 1966—the mission’s third day—Cernan exited the spacecraft and quickly found himself fighting his own equipment. His spacesuit was so rigid that even simple movements required intense effort. He struggled to complete the simplest maneuvers.

Within minutes, Cernan was exhausted and sweating profusely. His spacesuit was cooled only through the circulation of oxygen and as he worked to complete the goals of the EVA, his helmet fogged over completely, obstructing his view and his heart rate rose to about 180 beats per minute. As concerns grew that he might lose consciousness, the EVA was called off and Cernan’s spacewalk ended after two hours and eight minutes.

When Gemini IX-A returned to Earth, doctors found that Cernan had lost 13 pounds during the three-day mission, most of it water lost during his EVA.

The challenges Cernan faced that day reshaped NASA’s approach to spacewalking. His experience directly influenced improved training methods, refined EVA procedures, and precipitated advances in spacesuit design—key steps in preparing astronauts for lunar surface missions just a few years later.

Credit: NASA