Long-duration space flights and extraterrestrial colonizing magnify physiology challenges for the voyagers involved, including debilitating loss of muscle and bone mass. The musculoskeletal changes are primarily from acclimation to a microgravity environment and can cause a loss of over 30% of muscle mass in less than 6 months. Of all warning signs of functional decline, the most intuitive is physical changes in appearance or body shape. Astronauts returning from long-duration flights share frailty characteristics of sarcopenia, cachexia, and may develop osteoporosis while on Mars resulting in vertebral or hip fractures and hyperkyphosis. From studies in older adults, we know that frailty puts individuals at higher risk of falls (40%), hip fracture (25%), and death (82%) independent of age, health status, medical condition, functional status, mental symptoms, cognitive function and bone density for all BMI categories even for ages beyond 80 years. Those with sarcopenia are at 50% higher risk of falls than their peers.

In this project, we propose to monitor frailty risk using 3D optical scans with adjustment for fluid redistribution. 3DO models accurately estimate bone and body composition but lack space acclimation experience. We will perform studies to select hardware, algorithms, and augment models with microgravity analogs. We conclude with making a space-feasible prototype for microgravity testing during parabolic flights.


The long-term goal of Astro3DO is to create a space-feasible device and method to quantify astronaut fragility and risk of fractures from falls.

Our central hypothesis is that current 3DO models of body composition can be adapted to space feasible hardware and challenges associated with acclimation to space.

Our specific aims are:

  1. Determine the optimal performance and space feasibility of 3D optical cameras to collect views of the body by a characterizing the resolution, framing rate, precision of acquisition, and contrast detail characteristics using anthropomorphic phantoms.
  2. Explore and identify the accuracy and precision of 3DO derived total body composition (lean, fat, percent fat, BMD), special regions (visceral fat, subcutaneous fat, lumbar spine BMD) and automated anthropometry using pose varied, limited view scanning, analyzed with pose removed, compared to criterion methods (DXA and high resolution 3DO).
  3. Identify accuracy and precision limitations of 3DO body composition and automated anthropometry due to effects of space acclimation using surrogate conditions (poses, postures, inverted gravity (inversion boots), buoyancy (underwater) and microgravity (trampoline apex)).
  4. Construct and describe the performance of a space-feasible prototype under microgravity conditions during parabolic flights.

Research Team

John Shepherd, PhD

Principal Investigator

UH Cancer Center

Jean Sibonga, PhD

Biomedical Scientist, Science Lead, Bone and Mineral Lab

NASA Johnson Space Center

Peter Sadowski, PhD

Co-Principal Investigator

UH Manoa ICS Department

Aenor Sawyer, MD

Assistant Professor, Orthopedic Surgeon

UC San Francisco

Funding Source(s)