'A legacy of insights': Thornton served military and medicine as inventor, astronaut, professor FacebookTwitterEmail Dr. William Edgar Thornton, astronaut, inventor and medical professor, died Jan. 11 at his Fair Oaks Ranch home, with his wife by his side. He was 91.Courtesy photo Most people feel lucky if they can say they spent their career doing the one thing they really loved. For Dr. William Edgar Thornton, three would be the charm. Thornton, a retired astronaut, medical professor and inventor, died Jan. 11 at his Fair Oaks Ranch home, with his wife by his side. He was 91. “My father was an incredible man,” said his son Simon Thornton, of Fair Oaks Ranch. “He was an extremely caring father and set an example for his two sons.”