“I sat for a long time just thinking about what I’d been through. I couldn’t believe it had all happened. It had been a tremendous experience, and though I could not ever really share it with anyone, I looked forward to telling others as much about it as I could. I had made mistakes and some things had gone wrong. But I hoped that other men could learn from my experiences. I felt that the flight was a success, and I was proud of that.”
One of 110 candidates to be the nation’s first astronauts, Carpenter became an instant celebrity in 1959 when he was chosen as a Mercury astronaut. The Mercury 7 were Carpenter, Glenn, L. Gordon Cooper Jr., Virgil I. “Gus” Grissom, Walter M. Schirra Jr., Alan B. Shepard Jr., and Donald K. “Deke” Slayton.
Like his colleagues, Carpenter basked in lavish attention and public rewards, but it wasn’t exactly easy. The astronauts were subjected to grueling medical tests — keeping their feet in cold water, rapid spinning and tumbling and open-ended psychological quizzes. He had to endure forces 16 times gravity in his tests, far more than in space, something he said he managed with “great difficulty.”
“It was the most exciting period of my life,” he said.
Carpenter never did go back in space, but his explorations continued. In 1965, he spent 30 days under the ocean off the coast of California as part of the Navy’s SeaLab II program.
“I wanted, No. 1, to learn about it (the ocean), but No. 2, I wanted to get rid of what was an unreasoned fear of the deep water,” Carpenter told the NASA historian.
Inspired by Jacques Cousteau, Carpenter worked with the Navy to bring some of NASA’s training and technology to the sea floor. A broken arm kept him out of the first SeaLab, but he made the second in 1965. The 57-by-12-foot habitat was lowered to a depth of 205 feet off San Diego. A bottlenose dolphin named Tuffy ferried supplies from the surface to the aquanauts below.