FRESH AIR: While floating weightless in the International Space Station last spring, Commander Chris Hadfield recorded his own version of David Bowie’s “” — a video that’s now been viewed more than 18 million times on YouTube. But when he wasn’t busy being an Internet phenomenon, the Canadian astronaut was witnessing awe-inspiring beauty, facing life-threatening dangers and, at times, holding onto a spaceship orbiting Earth at 17,500 miles an hour. Hadfield has flown three space missions, conducted two space walks and spent a total of six months in space. On Earth, he’s been the chief of international space station operations in Houston and chief CAPCOM commander — the person at mission control who communicates directly with astronauts in orbit. In a new book, An Astronaut’s Guide to Life on Earth, he shares some of the lessons he learned in space. “There are no wishy-washy astronauts,” Hadfield tells Fresh Air’s Terry Gross. “You don’t get up there by being uncaring and blase. And whatever gave you the sense of tenacity and purpose to get that far in life is absolutely reaffirmed and deepened by the experience itself.” MORE

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