On October 29, 1998, the Space Shuttle Discovery blasted off on STS-95 with 77-year old John Glenn on board making him the oldest person to go into space. From the article:
"Oct. 29, 1998 - John Glenn Returns to Space
On October 29, 1998, the first American to orbit the Earth made history again. John Glenn became the oldest man to fly in space by serving as a payload specialist on STS-95 aboard the space shuttle Discovery.
The nine-day mission supported a variety of research, including the deployment of the Spartan Solar Observing Spacecraft, the Hubble Space Telescope orbital systems test platform and several microgravity experiments from NASA Glenn (then Lewis).
Glenn spent most of his time in space participating in investigations on the aging process. Scientists recognize several parallels between the effects of spaceflight on the human body and the natural changes that take place as a person ages. Glenn's experiments were designed to test how his body responded to the microgravity environment. They focused on balance, perception, immune system response, bone and muscle density, metabolism, blood flow and sleep.
Joining Glenn on the shuttle were Mission Commander Curt Brown, Pilot Steve Lindsey, Mission Specialists Scott Parazynski, Steve Robinson and European Space Agency astronaut Pedro Duque, and payload specialist Chiaki Mukai from the Japanese Space Agency.
The flight aboard the shuttle was quite different from Glenn's first mission. It lasted nine days and orbited the Earth 134 times, traveling a distance of 3.6 million miles in 213 hours and 44 minutes. The landing was also different. The shuttle Discovery eased through re-entry at a mere 3 Gs, half of what he experienced aboard Friendship 7.
The mission concluded with a safe landing at the Kennedy Space Center in Florida."