
A week after her historic moon mission ended, NASA astronaut Christina Koch struggled to walk in a straight line during a blindfold test.
After posting a video showing her wobbling and nearly tipping over — nearly enough, in fact, that attendants jumped in ready to help — Artemis 2‘s Koch joked about her recovery on Instagram: “Guess I’ll be waiting a minute to surf again.”
In microgravity, she added, the brain learns how to ignore signals our body automatically generates when moving around. Astronauts thus face similar issues when returning to Earth as do people with certain medical conditions, including concussions and vertigo, which is where physical therapy — and a bit of humor, as evidenced by Koch’s smiles as she wobbled — is helpful.
NASA and its international partners have more than 25 years of experience doing long-duration missions on the International Space Station (ISS), while NASA and Russia’s Roscosmos (with some other countries) also have different space station experiences dating to the early 1970s. All of this time has accumulated into lived experience that astronauts can share, and which scientists can write about — and have, in thousands of research papers.
Microgravity changes are affected somewhat by duration. Koch spent only 10 days in space on Artemis 2, from the April 1 launch to splashdown on April 10. That’s far shy of her near-year on the ISS during her first mission, or the six months a station crew typically spends on board.
But scientists are nevertheless following her recovery, as well as that of the other Artemis 2 astronauts: NASA commander Reid Wiseman, NASA pilot Victor Glover and Canadian Space Agency mission specialist Jeremy Hansen. Koch, Glover and Hansen were the first woman, person of color and non-American to leave low Earth orbit, respectively.
There are lots of things weightlessness disturbs, even in the short run. Microgravity messes with your notion of “up” and “down,” as well as your proprioceptive system that helps your body distinguish where your limbs are located. Over weeks and months, physical problems accumulate: calcium leaches from the bones, muscles lose mass, and some newer studies have examined subtle changes in genes.
The ISS, however, also has countermeasures to help with this — various exercise machines for weightlifting and cardio, drugs to slow down various types of deterioration, and consultations with doctors to monitor changes. And these were used, in mini-form, on Artemis 2: a balanced diet, supplements and a small “flywheel” device for cardio and weightlifting were some of the help astronauts received. They also could call home for medical advice if needed.
Mental health for space living can also be tough. While leaving Earth is an immense privilege, being far away from friends and family for long stretches is difficult. Add to that the stresses of living in a small environment with other people and trying to accomplish a lot of tasks in a habitat that is isolated and dangerous.
The Artemis 2 astronauts also came under more scrutiny than the typical ISS crew, partly because they were the first people to visit the moon in nearly 54 years, and partly because they gladly consented to hours of livestreaming their activities per day (a non-typical practice on station missions, aside from the occasional spacewalk).
Koch, who knows about small-space living from long stays both in Antarctica and in space, wrote on April 18 that she, aware of the risks, was not scared of her mission in the days before leaving. But she said her “humble little life” was the thing that is most important to her. “A part of me started to miss it terribly for the small chance in the future that could come to be,” she wrote.
With that mindset, she next shared on Instagram how grateful she was for a cup of coffee on the porch with her best friend.
That action, Koch added, “is a simple and universally small thing. But it is also everything.”


