Why Am I Taller?What happens in space that causes the body to change? Learn about life in space from astronauts. Is the human body built for Mars? NASAs studies on the International Space Station show we need to fix a few things before sending people to the Red Planet. Astronauts go into space with good vision and come back needing eyeglasses. Cognition and DNA expression could be affected for years. And then theres the discomfort of living in a tight space with