Peggy Whitson completed a six month tour of duty aboard the International Space Station as the ISS Commander for Expedition 16 in April 2008. She was first woman to command the International Space Station.

As the Expedition 16 Commander, Peggy Whitson participated in a seven hour, ten minute spacewalk. During the spacewalk, Whitson and astronaut Daniel Tani, the flight engineer, replaced a motor at the base of one of the station's solar wings.

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