Astronauts often have to deal with bone and muscle loss, vision issues, sleep difficulties, and increased risk of cancer. While such problems can be serious, they don’t necessarily occur in everyone. So when Scott Kelly was selected to be in the first year-long mission on the International Space Station, he and his brother Mark realized they were in a unique position to test just exactly how susceptible to health concerns a person in space might be. While Scott is in space, Mark will serve as the “control” here on Earth. Both twins will give blood and saliva samples, assessments of their vision, sleep, and cardiovascular state, and measurements of their bone mass.
via Geekosystem
