Peggy Whitson – With a total of 675 days, she also holds the record for the most days for American astronauts; across various missions, Peggy spent time on long-duration stays in the ISS and also traveled recently with Axiom Space.
Sunita “Suni” Williams – I suppose she served about 608 days on space missions, one being delayed for 286 days by ISS and later complications of the spacecraft.
Jeff Williams- 534 days through several missions to the ISS, the commander and leader in maintenance.
Mark Vande Hei- 523 days in space, including 355 days in one stretch aboard the ISS, a record.
Scott Kelly– His 340 days aboard the ISS during the 2015-16 period on one mission held the record of the longest-term US astronaut; his total time is 520 days.
Frank Rubio holds the title for the longest-ever single-mission flyby of a U.S. astronaut, 371 days aboard the ISS.
Christina Koch- Held the female record for one single mission at 328 days.
Barry Wilmore- Held a Total of 462 days, including the extended 286-day mission.
Mike Barratt- 447 days, during two ISS missions that included work in medical research.
Shane Kimbrough- Held 388 days in orbit through three launches and a series of spacewalks.
Why It Matters
The longer the stay in space, the more it allows scientists to study the effects of microgravity on humans. This research will prove very useful for future Mars and other much farther missions on Earth. The very endurance demonstrated by these NASA Astronauts shows that man can indeed adjust inside the restricted and isolated world of the ISS.
Final Note
These top 10 NASA Astronauts were true pioneers of long-duration spaceflight. From single-mission records to cumulative totals, their acts of courage and determination inspire all of us. Raising the bar of possibilities is the longest duration of 675 days by Peggy Whitson and 371 days by Frank Rubio.
