The prime mover behind NASA’s sports fitness program, the man to whom astronauts turn for advice about exercising and injuries and the man whose work over the past 17 years has prepared the way for the first civilians in space (see box, p. 56) is Dr. William Thornton, 55. With 10 or 12 of his instruments in use on space shuttle flights—from a device to measure the effect of weightlessness on growth in height to an optokinetic instrument that checks how the eyes are affected by space sickness—he is known around NASA as a combination of Edison and Einstein. Add to that a touch of Buck Rogers. In August 1983 aboard the shuttle Challenger, he became, at age 54, the oldest person ever to fly in space.
“If Captain Kirk had wanted the most knowledgeable and dedicated physician in the universe, perhaps second only to Mr. Spock in intelligence, he would have chosen Dr. Bill for his Star Trek,” says Dr. Tom Moore of his NASA colleague. Notes astronaut Mary Cleave, who has consulted him about improving her grip strength, “He takes out his little computer etchings and starts talking to you about your reach. He’s a doctor, but—let’s face it—he thinks like a physicist.”
Indeed, Dr. Bill has two fundamental laws of Thornton-dynamics: “Muscle in space is no different from muscle on earth” and “Use it or lose it.” Both principles underlie his development of the first treadmill used for exercise in space. In 1973, when Skylab 2 astronauts returned to earth after 28 days with considerable muscular deterioration, NASA’s prescription for Skylab 3 astronauts was a stationary bicycle. But Thornton argued that the bicycle ergometer did not provide enough force on leg muscles. When post-flight tests proved that, despite exercise on the bicycle, leg strength was down 25 percent, he got the go-ahead for a treadmill aboard Skylab 4.
It turned out to be something of a Rube Goldberg contraption, with a tread of kitchen Teflon. “I took a harness that didn’t work on the bicycle ergometer,” he explains, “and hooked heavy rubber bungees [elastic cords] as a substitute for gravity to pull the astronauts down on the device in weightlessness.” With its incline of about 30 degrees, astronauts in cotton stockings felt like “they were climbing an icy hill.” They dubbed it “Thornton’s Revenge.” But, says former astronaut Joseph Kerwin, “that third crew came down after 85 days with half the muscle weakness of the first crew. It was a triumph.”
The son of a small landholder in Faison, N.C., Thornton “was always doing electronics, flying and science even as a child,” says lifelong friend Anna Stroud Taylor. Eleven years old when his father died, Thornton, called “Moose” because of his 6’1″ height, began doing odd jobs and in high school opened a radio repair shop that later financed his education at the University of North Carolina. (He graduated in 1952 with a B.S. in physics.) During a stint in the Air Force, he patented the first of his 19 inventions—a missile scoring system that determined if planes shooting at targets had hit them or not. Then he attended UNC’s medical school, where he participated in cardiovascular research and invented the first computer for continuous analysis of EKGs.
A symposium at the Air Force’s Aerospace Medical Division in San Antonio turned Thornton on to space medicine. “Al Shepard had just made his flight and it was too good of a show to miss,” he says. “Though I didn’t tell anybody, by then I had decided I wanted to get a ride in space myself.” Since NASA at that time had age limits and wasn’t taking on any scientist-astronauts, Thornton signed up for the Air Force’s space medical research project in 1964.
In 1967 Thornton became one of a group of scientists admitted to the astronaut corps. His research on the effect of weightlessness on body fluids revolutionized medical awareness of heart and circulatory system functions in space. His mass-measuring instrument to “weigh” man in space was another first, establishing that astronauts were underfed and thus losing weight during space flight.
Finally, in 1983, six months before the flight of Challenger, he was called up as a last-minute member of the crew—mainly to investigate space sickness. “The only problem I had with Bill,” says ship captain Richard Truly, “was dragging him away from his work so he would look out at the beautiful view of the stars and Earth.”
With his next trip scheduled for January 1985, aboard the second Space Lab, Thornton is working 14-hour days with Dr. Moore to prepare more experiments on space motion sickness. His energy is an inspiration both aloft and on the ground. President Reagan radioed to him in space during his 1983 mission, “Bill, as the oldest astronaut, you have an especially warm place in my heart. It makes me think some day I might be able to go along.”