Bones and Stones in Space—Integrating the Medical and Scientific Questions

Bone loss and muscle atrophy are two consequences of long-term spaceflight, and neither the underlying mechanisms nor effective countermeasures have yet been found. Experiments designed for space station and beyond incorporate a number of scientific objectives focused on two interrelated concepts, calcium homeostasis and bone homeostasis. The experiments to be done require a trade-off between ground based analysis of samples and development of instruments to do these studies inflight. The scientific community is currently in the process of defining which scientific objectives can be accomplished inflight and what instrumentation is required to do this.