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Follow astronaut Scott Kelly's 12-month mission on the International Space Station, from launch to landing, as NASA charts the effects of long-duration spaceflight by comparing him to his identical twin on Earth, astronaut Mark Kelly.
Follow astronaut Scott Kelly's 12-month mission on the International Space Station, from launch to landing, as NASA charts the effects of long-duration spaceflight by comparing him to his identical twin on Earth, astronaut Mark Kelly.