NASA Commentator Dan Huot talks with Dr. Steven Boyd of the University of Calgary, the principal investigator of the TBone experiment on the International Space Station, which is taking advantage of a new technique to learn how spaceflight affects the quality of bone after prolonged exposure to weightlessness. Using three-dimensional high resolution peripheral quantitative computed tomography, the investigation measures bone density and structure so scientists can distinguish changes in bone health and strength that result from microgravity or extended periods of immobilization.