For more than 40 years, ultrasound has remained the only method of medical imaging in space, but not by choice. Astronauts require extensive training to operate the equipment, and the technique relies on the transmission of sound waves, something particularly difficult to maintain in a cramped, noisy environment.

“It has been a dream for aerospace medicine to have more than one imaging modality to diagnose diseases and injuries in space,” explained Mayo Clinic researcher Sheyna Gifford.

So why haven’t crews started carrying X-ray devices for their missions? X-ray machines are heavy and generate considerable amounts of radiation, while subjects must remain very still during imaging.

“Because everything in space is constantly moving, it was believed that obtaining a diagnostic image in orbit was too technically difficult,” Gifford added.

These limitations of the past are finally disappearing. Commercial X-ray machines on the market, such as the cooler-sized MinXray TR90BH, now allow users to perform scans on subjects far from traditional facilities. In 2022, Gifford helped prepare a crew to successfully generate digital X-rays while experiencing microgravity during parabolic flight. Gifford’s team then spent years collaborating with SpaceX to plan another feasibility study. This time they didn’t want to operate an X-ray machine aboard an airplane that simulated conditions in space; They intended to use the equipment during an orbital mission.

The process was detailed in a study recently published in the journal Radiologyand focuses on last year’s Fram2 mission. Instead of days of medical training, the astronauts spent just four hours learning how to use their portable x-ray device. They then took pre-check X-rays of a hand, forearm, chest, abdomen and pelvis before the launch of the SpaceX Falcon 9 rocket on March 31, 2025. Once in orbit, the team calibrated the system before testing their MinXray on the same body parts, as well as on a smartwatch.

Once the crew returned, a trio of independent radiologists reviewed the orbital X-ray images based on their positioning, spatial and contrast resolutions, and overall scan quality. Although the positioning scores decreased slightly for the central body images, all other scans held up against similar examples created on Earth. Meanwhile, astronauts reported that using the machine was easy despite minimal prior training.

“Acquiring diagnostically useful X-rays in space is something anyone can do,” Gifford said. “Three very talented non-medical people with four hours of training in one of the most hostile environments did it well and did it well.”

Looking ahead, researchers hope to conduct more X-ray tests during orbital missions, while continuing to reduce the overall size of the equipment. According to Gifford, the implications go beyond medical emergencies.

“For a sustained human presence in space, X-rays are critical not only for crew members but also for other mission components, such as electronics and spacesuits,” he said. “The only way to look inside these objects without taking them apart is to x-ray them.”

Before astronauts install X-ray machines on the Moon, there is at least one issue that requires immediate attention. While it remained useful during the mission, Fram2 astronauts reported that their machine suffered relatively minor exterior damage during takeoff and landing.

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