A NASA Flight Surgeon Reveals the Science of Aerospace Medicine

Recently, NPR published an insightful article highlighting the journey home of NASA astronauts Butch Wilmore and Suni Williams after an extended mission aboard the International Space Station.

While the astronauts' splashdown captivated public attention, their return journey reveals a lesser-known story—how aerospace medicine specialists meticulously orchestrate the astronauts' transition back to Earth's gravity.

The Medical Team Behind Space Missions

Natacha Chough, MD, MPH, NASA Flight Surgeon and Clinical Assistant Professor in UTMB’s Aerospace Medicine Division, provides a rare glimpse into the interdisciplinary teamwork behind astronaut rehabilitation.

"Just as professional sports teams have team doctors, there is a group of team doctors who specialize in Aerospace Medicine, known as Flight Surgeons, who care for the astronaut corps," Dr. Chough explains.

Despite their title, these specialists don't perform surgeries or fly in space. Instead, they provide critical ground-based medical support, ensuring astronaut health and safety throughout all mission phases.

Retraining the Body After Weightlessness

Transitioning from weightlessness back to Earth's gravity creates unique physiological challenges requiring carefully structured rehabilitation. Dr. Chough highlights the crucial role of specialized rehabilitation professionals:

"There is an incredible group of dedicated athletic trainers and physical therapists who manage and implement the post-flight rehabilitation for crew. This starts the very next day after landing and involves two hours per day for six weeks of progressive physical training."

This intensive regimen helps astronauts rebuild balance, coordination, and core strength—all systems that become relatively dormant during extended microgravity exposure. "Your balance and neuromuscular coordination require re-training because in weightlessness, your brain becomes almost entirely dependent on your visual input for orientation," Dr. Chough elaborates.

“If you ask a returned astronaut to stand with their eyes closed in the early post-landing phase, they can have difficulty keeping their balance when that visual input is taken away, because their inner ear and cerebellum, both of which rely on gravity for inputs and normally assist the eyes with balance, coordination, and orientation, haven’t been as active while in space.”

She notes that important recovery milestones, such as regaining pre-flight baseline balance, typically occur within 7 to 10 days, allowing astronauts to resume everyday activities like driving.

Reality vs. Hollywood: Space Medicine Myths

Many misconceptions about spaceflight medicine stem from dramatic portrayals in popular media, where medical emergencies are often exaggerated for dramatic effect or important preventive measures are omitted entirely.

"Overall, in-flight medical issues tend to be over-exaggerated or under-represented, probably because they aren't as exciting for the silver screen," Dr. Chough observes.

Contrary to Hollywood portrayals, NASA has never had to return an astronaut early from space due to medical issues—a testament to the rigorous preventive approach at the heart of aerospace medicine.

This achievement reflects years of meticulous preparation, similar to how the FAA works to ensure pilot safety and medical fitness for duty. The aerospace medicine team focuses primarily on prevention, considering emergency response as a secondary, though still essential, component.

The most crucial work happens long before launch day. Dr. Chough's team spends months, and sometimes years, consulting with specialists to optimize management plans for any existing health conditions, developing procedures and contingency plans in case a condition worsens, validating medical kits, and training crew members on their use. This thorough preparation, rather than dramatic emergency interventions, is what truly defines aerospace medicine's success.

Medical Innovation for Space Travel

Ongoing technological advancements continue to transform aerospace medicine, with particular emphasis on equipment optimization. Space healthcare demands solutions that terrestrial medicine rarely encounters due to the extreme constraints of spacecraft environments.

For Dr. Chough, "medical devices that are smaller, lighter, and consolidate multiple functions generally will get good marks because we have limited mass and volume to work with when it comes to the medical capabilities available onboard a crewed spacecraft."

The limitations of space travel drive constant innovation in medical technology. Weight restrictions mean that multipurpose equipment is highly valued, creating unique design challenges for medical engineers.

The same innovative approaches that solve problems for astronauts often lead to advancements in portable medical technology used in remote locations on Earth, such as disaster zones, wilderness expeditions, and underserved communities.

As humanity contemplates even longer journeys to Mars, these innovations in medical technology and protocols will face their greatest test yet.

Preparing for Mars: New Medical Frontiers

Looking toward future Mars missions, aerospace medicine faces unprecedented challenges that extend far beyond those encountered in low Earth orbit. These multi-year journeys will test human physiology and psychology in ways that current space medicine protocols must evolve to address.

Communication delays represent one of the most significant hurdles. Unlike ISS missions where real-time consultation with Earth-based medical teams is possible, Mars crews will need greater autonomy in medical decision-making. As Dr. Chough explains, waiting for direction from Mission Control simply won't be practical.

This autonomy raises complex questions about crew composition and medical expertise. Should medical providers become mandatory crew members? "But what if the provider is the one who gets ill or injured? Do you send two providers? Do you send two of every role on the crew for redundancy? You can see how this quickly becomes a slippery slope," Dr. Chough points out.

Even seemingly minor considerations like crew size carry significant implications for group dynamics and conflict resolution. An even-numbered crew risks deadlocked decisions, while odd numbers create the potential for single tie-breakers who might face resentment from their fellow crewmates.

These interpersonal factors, alongside technical challenges like radiation exposure, demonstrate why Mars missions require entirely new approaches to aerospace medicine.

The Psychological Journey Home

Psychological support represents another vital aspect of astronaut recovery, particularly following long-duration missions. NASA recognizes this importance by maintaining a dedicated Behavioral Health and Performance team to address these unique challenges.

The psychological adjustment astronauts face parallels what military personnel experience following overseas deployments.

During missions, astronauts miss significant life events—holidays, family milestones, even births and deaths. Meanwhile, their families adapt to new roles and routines in their absence.

"There can be a readjustment period for everyone involved when crew return home," Dr. Chough explains.

While isolation is often discussed as a defining characteristic of spaceflight, Dr. Chough notes that similar isolation occurs in Antarctic expeditions and other remote environments.

What truly sets the astronaut experience apart is the profound psychological impact of seeing Earth as a fragile blue marble against the vastness of space.