Quick answer (updated October 16, 2026): Jessica U. Meir is an American NASA astronaut, scientist and former marine-biology researcher. She flew to the International Space Station (ISS) in September 2019, took part in the first all-woman spacewalk with Christina Koch on October 18, 2019, and later commanded NASA’s Crew-12 mission in 2026. According to NASA’s official biography, she returned from Crew-12 in October 2026. Her career links scientific research into how animals tolerate extreme conditions with the everyday demands of human spaceflight.
Who is Jessica Meir?
Jessica U. Meir was born in Caribou, Maine, and became a NASA astronaut after years studying animals that operate in challenging environments. Her work included investigations of diving physiology in penguins and seals and the ability of bar-headed geese to fly at high altitudes where oxygen is scarce. Those fields matter to space medicine because astronauts also have to function in environments that stress breathing, circulation and the body’s normal adaptation systems.
NASA selected Meir as part of its 2013 astronaut class. Before flying, she completed astronaut training, including work with spacecraft systems, robotics, International Space Station operations and survival procedures. She eventually served two long-duration assignments aboard the orbiting laboratory, one in 2019–2020 and a second in 2026.
Jessica Meir’s space missions: key dates
| Mission | Dates | Role and major work |
|---|---|---|
| Expeditions 61/62 (Soyuz MS-15) | September 25, 2019 – April 17, 2020 | ISS flight engineer; station science; three all-woman spacewalks with Christina Koch |
| NASA SpaceX Crew-12 (Expeditions 74/75) | February 13 – October 8, 2026 | Crew-12 commander; ISS science, operations and additional spacewalks |
For mission-day details, spacecraft status and recovery reporting, consult NASA’s mission archives rather than relying on speculative social-media launch dates. Our separate Crew-12 splashdown explainer discusses the return event; this profile focuses on Meir’s background and accomplishments.
What happened on the first all-woman spacewalk?
On October 18, 2019, NASA astronauts Jessica Meir and Christina Koch exited the ISS together. NASA describes this as the first spacewalk performed entirely by women. Their primary task was to replace a faulty battery charge/discharge unit that helped distribute power from the station’s solar arrays. The spacewalk lasted approximately seven hours and 17 minutes.
The achievement was notable both as a milestone in representation and as an ordinary piece of critical orbital maintenance: the astronauts wore NASA extravehicular mobility units, used safety tethers and tools, and followed detailed steps planned with ground controllers. A spacewalk is not a free flight in space; astronauts work outside the station while remaining connected and protected by their spacesuits. NASA’s historic spacewalk report explains the planned maintenance and contemporary mission context.
How many spacewalks did Meir make on her first flight?
Meir completed three spacewalks during her 2019–2020 stay, all with Christina Koch. NASA credits those outings with a combined duration of approximately 21 hours and 44 minutes. The later 2026 Crew-12 mission added more EVA experience; NASA’s updated biography reports four spacewalks and about 27 hours and 38 minutes for that assignment. Treat those figures as mission-specific, not interchangeable totals.
What did Jessica Meir do on Crew-12 in 2026?
Meir returned to the ISS as commander of NASA’s SpaceX Crew-12 mission. The mission launched on February 13, 2026 and included NASA astronaut Jack Hathaway, European Space Agency astronaut Sophie Adenot and Roscosmos cosmonaut Andrey Fedyaev. They joined the station’s Expeditions 74 and 75 during their mission.
The Crew-12 astronauts supported scientific experiments, station maintenance and international operations. Research aboard the ISS encompasses biological systems, materials and physical sciences, Earth observation and technologies that may help longer flights. Different crew members have different roles, so it would be inaccurate to attribute every station experiment to Meir personally.
According to NASA’s official biography, Meir returned to Earth on October 8, 2026, closing a roughly 237-day mission. Her second stay included four spacewalks. The agency’s own mission statements and astronaut record are the preferred sources for these rapidly changing career totals.
Education and research before NASA
Meir studied biology at Brown University, earned a master’s degree in space studies through the International Space University, and completed a doctorate in marine biology at the Scripps Institution of Oceanography, University of California San Diego in 2009. She worked on comparative physiology: the study of how bodies function across different species and living conditions. Her research drew attention because some animals routinely survive changes in pressure or oxygen availability that would be difficult for most humans.
Studying these animals is not the same thing as conducting experiments on astronauts. The connection is in the biological questions: how breathing, blood circulation, oxygen delivery and fatigue change under unusually demanding conditions. Later, as an astronaut, she moved from field and laboratory research to space station operations and investigations in microgravity.
Why Jessica Meir’s achievements matter
Three themes distinguish Meir’s career. First, her route into space shows that NASA recruits scientists from fields beyond aerospace engineering, including biology. Second, the 2019 all-woman EVA marked a visible change in the history of space operations without diminishing the practical importance of the maintenance work. Third, commanding Crew-12 in 2026 demonstrated how astronaut careers can span multiple station expeditions and years of preparation between flights.
Those milestones should not be exaggerated into claims that Meir was the first woman in space or the first woman to lead an ISS expedition. Earlier astronauts achieved those different milestones. The accurate distinction is that Meir and Koch performed the first all-woman spacewalk together in 2019, and Meir served as Crew-12 commander in 2026.
Frequently asked questions
Is Jessica Meir a NASA astronaut?
Yes. NASA selected her as an astronaut in 2013. She has worked on ISS Expeditions 61/62 and 74/75, with her second trip aboard Crew-12.
Was Jessica Meir the first woman to spacewalk?
No. Soviet cosmonaut Svetlana Savitskaya completed the first spacewalk by a woman in 1984. The milestone involving Meir is the first all-woman spacewalk, completed with Christina Koch on October 18, 2019.
How long was Jessica Meir’s first space mission?
NASA records approximately 205 days for her September 2019 to April 2020 ISS mission. Her Crew-12 expedition in 2026 was a separate, longer assignment.
Which subjects did she study?
She studied biology, space studies and marine biology. Her work investigated the physiology of diving and high-altitude animals, an unusual scientific background for a highly trained spaceflight operator.
Did Jessica Meir fly on Artemis II?
No. Her documented missions in this profile were long-duration International Space Station expeditions, including Crew-12. It would be incorrect to substitute an Artemis crew assignment without an official NASA announcement.
Official sources and further reading
The most reliable primary reference for Meir’s career details and cumulative spaceflight record is NASA’s Jessica U. Meir astronaut biography. For the 2019 milestone, see NASA’s historical report on the all-woman spacewalk. Crew and mission dates should be cross-checked against NASA’s Crew-12 announcements when planning time-sensitive coverage. This article was reviewed on October 16, 2026.
