Two days before Saturday’s space shuttle Columbia tragedy, the School of Medicine presented a lecture by astronaut and surgeon Scott Parazynski, MD, whose experiences include several NASA missions.

Parazynski graduated from Stanford medical school in 1989. While his peers embarked on their medical careers Parazynski followed a more unusual direction when he was selected by NASA as an astronaut in 1992.

Parazynski described his experiences as part of four space missions during a grand rounds talk on Thursday. His experiences include a trip to Mir Space Station, one to the International Space Station, and one mission in which he was in charge of monitoring aging research with crewmate and former U.S. Sen. John Glenn.

As an astronaut, Parazynski said that he had to become a generalist. Although he has performed life-sciences research that calls upon his medical training, he has also done research on global ozone distribution and participated in two space walks to repair or upgrade spacecraft, including installing and testing a robotic arm.

"There’s no way to describe the view when you are out on a space walk," he said. For the most part, he and his partner were so focused on the task at hand that it was like being back in the pool where they practice for space walks. "Then you look up and you see the earth and realize where you are," he said.