Record-breaking astronaut Peggy Whitson retires from NASANASA's most experienced astronaut has hung up her space boots.
Peggy Whitson, who holds the record for the most time in space by an American, resigned from the space agency on Friday (June 15).
"It's been the greatest honor to live out my lifelong dream of being a NASA astronaut," Whitson posted on Twitter on Friday. "Thank you to the 'NASA Village' and all who have supported me along the way. As I reminisce on my many treasured memories, it's safe to say my journey at NASA has been out of this world!"