Peggy Whitson Just Became the Oldest Female Astronaut in Space

Over the weekend, 56-year-old Peggy Whitson of the National Aeronautics and Space Administration (NASA) officially became the oldest female astronaut to travel in space, after arriving at the International Space Station on what is now her third mission.

According to NPR, Whitson was commander of the second of her first two missions and will likely become commander again for her current one, having spent over a year "off-planet."

"When Whitson lands back on Earth in spring of 2017, she'll have amassed more time in orbit than Jeff Williams, who set a new U.S. mark in September with total off-planet time of 534 days," NPR reports.

Whitson will celebrate her 57th birthday in space on February 9, 2017.

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Photo Credit: REUTERS/Shamil Zhumatov