Astronaut Scott Kelly and Russian cosmonaut Mikhail Kornienko are spending a year living aboard the International Space Station to help NASA learn more about the effects of long-term space travel on the human body.
YEAR IN SPACE STUDY KEY QUESTIONS:
How will astronauts perform mentally and physically after a year in space?
What changes are there to brain structure and sensory/motor abilities?
How do bodily fluids shift?
How are visual acuity and eye health affected?
How do the blood vessels change?
What is the risk of osteoporosis (brittleness of bones) and bone fracture?
How do microorganisms within the body change?
TWINS STUDY KEY QUESTIONS:
Does space travel accelerate atherosclerosis?
How do an individual’s genes affect fluid shifts and vision degradation?
How does space travel affect the genes, chromosomes, DNA and RNA?
How does space travel affect the immune system?
Source SPACE.com: All about our solar system, outer space and exploration.
Source: http://www.space.com/28931-one-year-space-mission-explained-infographic.html