Measuring the body in orbit with ultrasound
Bone, muscle, blood vessels and the eye all change within weeks of leaving Earth. Most of what we know about those changes comes from measurements taken before launch and after landing. We are building an ultrasound system that a crew wears instead of operates, so the record runs through the mission itself.
Why ultrasound
A habitat has no room for MRI or CT. Both are large, heavy and power-hungry, and CT adds radiation to a crew already exposed to more of it than anyone on Earth. Ultrasound is the only imaging method that fits in a habitat, runs on modest power and is safe to repeat daily.
It has flown before. Crews on the International Space Station have used ultrasound for years, and the eye and the jugular vein are two of the places it has shown changes that ground-based tests missed. What has changed is the hardware. Chip-based probes, of the kind Butterfly Network makes, have brought a scanner that once filled a cart down to the size of a phone.
The operator problem
On the station today, a crew member holds the probe on their own body while a sonographer on the ground guides them by voice. The result depends on how well the probe is placed and held, and every session costs crew time. That limits ultrasound to occasional checks, and occasional checks cannot show how a change develops.
Our system removes the operator. The probe is worn, positions itself against fixed landmarks on the body, and runs the same scan the same way every session. Consistency matters more than any single image: two scans are only comparable if they were taken the same way.