NASA sent a 77-year-old payload specialist back into space in 1998, 36 years after he became the first American to orbit Earth - not just to make history again, but to study how an older human body responds to microgravity, becoming the oldest person ever to fly in space

John Glenn returned to space aboard the shuttle Discovery in 1998. He became the oldest person to travel into space at age seventy-seven. NASA utilized his flight to study aging and spaceflight connections. The mission conducted over eighty scientific experiments during its nine days. Glenn's journey marked a historic return to the environment that made him a hero.

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