NASA astronaut Peggy Whitson, who holds the U.S. record for most cumulative time in space, is retiring after 22 years in the astronaut corps and three tours of duty on the International Space Station.
Whitson, 58, became the station’s first female commander in 2007, the first woman to head the Astronaut Office in 2009, and the oldest woman to fly in space in 2016. She also holds the record for most spacewalks by a woman (10).
Her total in-space time of 665 days — gained during space station stays in 2002, 2008 and 2016-2017 — puts her on top of the list for NASA astronauts. Only six spacefliers, all Russians, rank higher.