Whitson spent 665 days in space over three space station missions
Peggy Whitson, who holds the U.S. record for most cumulative time in space, announced her retirement on Friday.(NASA)
The 58-year-old biochemist, who grew up on a Iowa hog farm, joined NASA as a researcher in 1986 and became an astronaut in 1996. Her last spaceflight, spanning 2016 and 2017, lasted close to 10 months.
Only Russian men have spent more time in space: Gennady Padalka holds the record with 879 days over five missions.
NASA Administrator Jim Bridenstine called Whitson an inspiration, citing her determination and dedication to science, exploration and discovery.
Whitson works during a spacewalk outside the International Space Station on Jan. 6, 2017. (NASA via AP)
“She set the highest standards for human spaceflight operations,” Brian Kelly, director of flight operations at Johnson Space Center in Houston, said in a statement, “as well as being an outstanding role model for women and men in America and across the globe.”
Before leaving the space station last September, Whitson said she would miss the orbiting outpost — an “awe-inspiring creation” — and the views from 400 kilometres up.
“I will miss seeing the enchantingly peaceful limb of our Earth from this vantage point. Until the end of my days, my eyes will search the horizon to see that curve,” she said.