CAPE CANAVERAL, Fla. – Butch Wilmore and Suni Williams of NASA are not the first to experience extended stays in space, although their 9 ½-month mission isn't the longest on record.
However, the transformation of a brief journey into a prolonged stay is unprecedented.
The pair embarked on a test flight aboard Boeing's Starliner capsule last June, initially scheduled for eight days. Upon their SpaceX return on Tuesday, they had spent 286 days in space—36 times longer than planned.
According to NASA's space operations director, Ken Bowersox, “Mathematically, the extension represents the largest percentage increase over the original mission duration.”
Bowersox, also a former astronaut, experienced a sudden extension of his own space station mission. He and Don Pettit, currently on the orbiting lab, were in space when the Columbia shuttle disintegrated during reentry in 2003, resulting in the death of all seven crew members and a two-year grounding of the shuttle fleet.
Bowersox noted, “The reasons for our extended stay were tragic,” referring to his mission's extension from four to over five months.
Here’s a recap of other space travelers who found themselves in extended missions—whether by choice or circumstance—along with interesting spaceflight statistics.
NASA astronaut Frank Rubio's mission doubled from 6 to 12 months after his Russian Soyuz capsule, docked to the space station, sustained a micrometeorite impact and lost its coolant. In 2023, a replacement capsule was sent to bring Rubio and his two Russian colleagues home. His 371-day journey marks the longest spaceflight by an American. Scott Kelly, NASA's first year-in-space astronaut, spent 340 days on the space station in 2015 and 2016. His twin brother, U.S. Senator Mark Kelly of Arizona, also served as a NASA astronaut on shorter shuttle missions.
Russian cosmonaut Valery Polyakov spent 14 ½ months on the Mir space station in the mid-1990s. He volunteered to study the long-term effects of weightlessness on the human body and mind. His 437-day spaceflight remains a world record. Polyakov passed away in 2022 at the age of 80.
Christina Koch of NASA holds the record for the longest single spaceflight by a woman, with 328 days on the space station in 2019 and 2020. During that same mission, she and Jessica Meir performed the first all-female spacewalk. Koch is part of NASA's first Artemis crew, which will orbit the moon as early as next year.
Last year, Russian Oleg Kononenko became the first person to surpass 1,000 days in space over his career. By the time he returned from the space station last fall, he had accumulated 1,111 days across five spaceflights—over three years. Former NASA astronaut Peggy Whitson is America’s most experienced space traveler, with 675 days from three station missions and a private Axiom Space trip. She is scheduled to lead another Axiom crew to the space station this spring. Williams' delayed return places her second with 608 days in space over three missions.
Williams' extended mission made her the world’s most experienced female spacewalker. She conducted two spacewalks earlier this year for station upkeep, increasing her career total to 62 hours. Across three space station missions, she has performed nine spacewalks, one less than Whitson, although Whitson's spacewalks totaled 60 hours.
Retired Russian cosmonaut Anatoly Solovyev holds the record with 16 spacewalks, totaling about 80 hours. Michael Lopez-Alegria, a retired NASA astronaut, is NASA’s spacewalking leader with 10 spacewalks and 67 hours.
NASA data indicates that 721 individuals have journeyed into space, including short-duration tourists and military X-15 pilots, with 102 being women. On April 12, 1961, Yuri Gagarin of the Soviet Union became the first person in space. Alan Shepard, the first American and Mercury astronaut, followed on May 5, 1961. Valentina Tereshkova, also of the Soviet Union, became the first woman in space in 1963, while Sally Ride became the first American woman in space in 1983. Tereshkova is the only one still living.
NASA lists 47 active astronauts, including 20 women. This list does not include astronauts who have transitioned to management roles within the agency.