biology

Welcome to the SpacEdge Academy lesson on the NASA Twins Study! In 2015, NASA conducted a huge study with identical twin astronauts, Mark and Scott Kelly. One astronaut (Mark) who had spent some time in space, later stayed on Earth while his twin brother (Scott) endured almost a year-long stay on the International Space Station. Scientists took biological samples and conducted tests on both twins to track the effects of long-term spaceflight on the human body.