Human Body in Space
Even though Yuri Gagarin had returned safely from orbit just three weeks earlier, NASA biomedical experts were still very concerned about how a human being would fare in the new environment of space. Shepard was subjected to every test, measurement, and probe the doctors could dream up—before, during, and after his flight. The doctors recorded every aspect of his physical state, dutifully noting the astronaut's loose toenail and peeling sunburn on launch day. He traveled into space with several sensors attached to his body, including one in his rectum for monitoring temperature.