To Joe Dervay, MD, it’s almost unfathomable that humans haven’t set foot on the moon in more than 50 years.
Dervay, a flight surgeon for the National Aeronautics and Space Administration (NASA) at the Johnson Space Center in Houston and president of the Aerospace Medical Association (AsMA), remembers growing up watching the Apollo lunar missions with awe and admiration.
His elementary school teachers “would literally stop a class and wheel in a black and white television,” Dervay recalls. “Everyone was riveted to watch the launches, the lunar landings, the splashdowns. … At a young age, I was very intrigued by space exploration.”
While various missions to space, particularly to and from the International Space Station (ISS), have continued through the decades, it is only within the last few years that plans to expand space exploration have accelerated. And with them, so has the demand for physicians and medical researchers with expertise in aerospace medicine, a specialty focused on the distinct impact of aviation and space travel on the human body.
“The future [of aerospace medicine] is bright,” Dervay says.
Over the last couple of years, private space travel has taken off, says Emmanuel Urquieta Ordonez, MD, an assistant professor at the Center for Space Medicine and chief medical officer at the Translational Research Institute for Space Health at Baylor College of Medicine in Houston.
In 2021, SpaceX, the spaceflight company founded by billionaire Elon Musk, made history by sending the first all-civilian crew into orbit. Since then, several private companies have also accelerated their space travel programs, including Blue Origin, started by Amazon founder Jeff Bezos, and Virgin Galactic, launched by Virgin Group founder Richard Branson. Virgin Galactic sent its first commercial crew into orbit on June 29.
This commercial version of the “space race” comes alongside NASA’s announcement of its ambitious Artemis mission plans, which include sending a crew to the moon again for the first time since 1972, establishing a base camp on the moon, and, eventually, sending humans to Mars.
NASA has said that the ISS will cease operation in 2030 to be replaced by multiple space stations run by private industry that will be used for both tourism and scientific research.
To keep up with the demand for people with expertise in aerospace medicine, academic medicine institutions have expanded their programs to prepare clinicians for this burgeoning industry. Five institutions now offer residencies in aerospace medicine, with 10 active residents as of 2022. In addition, some medical schools and teaching hospitals, including the Ronald Reagan UCLA Medical Center and the University of Colorado Anschutz Medical Campus, have recently started offering programs specifically focused on preparing trainees for future careers in human spaceflight.
“There’s never been a better time to be in the field of space medicine than today,” Urquieta says. “The opportunities are incredible.”
What is aerospace medicine?
Though a relatively small field, aerospace medicine has existed for nearly a century. The AsMA (known at its inception as the Aero Medical Association) was formed in 1929 after World War I accelerated advancements in aviation and it became apparent that the medical needs of pilots required an approach distinct from treating those who stay on land.
In 1950, after the U.S. Air Force School of Aviation Medicine established its Department of Space Medicine, several members of the association formed a constituent group to focus on the emerging field, according to the AsMA. Over the years, the field has expanded to encompass aviation and space medicine, as the environmental conditions present during both types of flights create similar challenges to health — including radiation exposure, exposure to G-forces, emergency ejection injuries, and low-oxygen and microgravity conditions.
“Because this is an environmental and occupational discipline, it cuts across every organ system,” says Robert Haddon, MD, an assistant professor of medicine at the Mayo Clinic College of Medicine and Science in Rochester, Minnesota, and program director for the Mayo Clinic’s Aerospace Medicine Fellowship. “In aerospace everything is in play.”
Generally, fellows admitted to the Mayo Clinic program start with significant experience in aviation or aerospace medicine already, but come from a variety of specialties ranging from internal medicine to psychiatry, he says. Because of the difficulty and expense of treating injury and illness in air — or, especially, in space — the emphasis in aerospace medicine training is on prevention. The American Board of Preventive Medicine, which accredits the programs, requires its fellows to earn a master’s degree in public health during their training.
In his role as a crew surgeon for NASA, Dervay has supported many missions to space, including Space Shuttle, long-duration stays at the ISS and the more recent Commercial Crew missions. This involves assessing the health of potential crew members to ensure they’re in optimal health for space travel; following selected crew members through their physical training, spacesuit pressure testing, mission simulations, and basic medical training, which can go on for more than a year before liftoff; remotely monitoring their health, exercise regimens, and psychological well-being throughout their time in space; and finally, preparing the crew for reentry, providing assessment and any medical care needed upon landing or splashdown.
Astronauts living in space for an extended period can experience a variety of physiological challenges. The lack of gravity, for example, will cause bone and muscle degradation at faster than normal rates compared to Earth, making daily aerobic and resistive exercise in space vital to counteracting losses.
“Crew members will tell you they feel exceptionally heavy initially upon return,” Dervay says.
They undergo a 45-day period of readaptation, including neurovestibular (balance) training and strengthening and conditioning to get them back to being able to live and perform normally on Earth. This period also involves extensive health monitoring and medical data collection.
“There’s a lot of science and medical testing going on upon return, which helps grow our knowledge base,” Dervay says.
Medical research in space and its impact on Earth
The practice of aerospace medicine goes beyond clinical care for the crew. Though only a small number of humans have experienced outer space, the impact of the space environment on their physiology can expand scientific knowledge for the general population.
“Every single thing that we look at in space flight has applications for Earth health care,” Urquieta says.
Scientists at Baylor collect genetic samples from astronauts before, during, and after spaceflight and use the institution’s genomic sequencing center to analyze how different genes react in the space environment, Urquieta explains. They’re also looking at pharmacogenomics — how a person’s genes influence how they respond to medications — to optimize effective pharmaceutical disease management during space travel.
Urquieta says that what they learn from delivering health care to astronauts during spaceflight under the most extreme conditions can help further develop the field of personalized medicine — which involves tailoring pharmaceuticals and other treatments for optimal effectiveness for a patient’s unique physiology.
One example of how technology originally adapted for spaceflight has benefited health on Earth is the advancement of the ultrasound machine. In the early 2000s, NASA researchers tested novel uses for ultrasound in diagnostics and remote monitoring from space. Their research and testing expanded the use of ultrasound in diagnostics for evaluations that previously required an X-ray or other less mobile equipment. In addition to developing new uses that are now standard at most hospitals, the NASA researchers created training modules to help nonexperts like astronauts accurately use an ultrasound machine for timely diagnosis in the field. They then adapted the training to be relevant here on Earth — for example, on-the-spot diagnosis of injuries to athletes and to those traveling to remote locations, such as Mount Everest or the Arctic Circle.
Furthermore, scientific research performed in space has helped advance understanding of Alzheimer’s disease, asthma, cancer, and osteoporosis, as well as the search for treatments, according to NASA.
Earlier this year, during a private astronaut mission to the ISS, researchers from the University of California San Diego Stanford Stem Cell Institute conducted experiments intended to help develop more effective cancer therapies. During an earlier mission, researchers found that cancer cells regenerate and resist standard therapies much more quickly in space than they do on Earth. This finding inspired researchers to use an accelerated timeline and organoid models to test how cancers like leukemia, colorectal cancer, and breast cancer adapt to resist therapies — in the hopes this understanding will help doctors anticipate cancer mutations on Earth.
And while research in space medicine has made promising strides, scientists still have many questions about how the space environment affects the human body. Up until this point, astronauts have been carefully vetted to be in peak physical health before embarking on spaceflight, so researchers have collected little data on how people with various health conditions and of different ages will react to space.
“The private astronauts who go to space are more representative of the population on earth: older people, young people, folks with medical conditions, people from different countries,” Urquieta says.
As spaceflight evolves in duration and types of missions undertaken, there will be much to learn, Dervay says. Research in these areas will prove particularly important as humans return to the moon, venture even farther into space, and make progress toward an eventual Mars landing.
A growing field of opportunity
For anyone with an interest in both medicine and space exploration, now is the time to get involved in the field of aerospace medicine, Urquieta says.
“There’s so much possibility, we’re very fortunate to be in this time of spaceflight,” he says.
Dervay emphasizes the need for clinicians from a variety of specialties to be engaged with the challenges of aerospace medicine. Currently, there are physicians with robust clinical practices focused on terrestrial medicine who are not directly employed by aerospace companies, but who use their expertise to consult with NASA or other spaceflight companies on a variety of medical issues.
Haddon echoes the need for future aerospace medicine experts to possess diverse skill sets: “Develop expertise in an area of medicine that you personally love, and learn to apply that to the aeromedical setting,” he says. “In order to really excel in aerospace medicine, you’ve got to be a good doctor.”
Adds Dervay, who serves as a mentor for aspiring flight and crew surgeons: “Aerospace medicine has been around for several decades … [but] there is no doubt, we are in our infancy of knowledge in many ways. … It’s important to encourage and recruit folks who are foremost excellent physicians who like to be challenged, are mission focused, and demonstrate creativity and innovation. We’re going to see some amazing science and exploration in the coming decades.”