A human expedition into space offers many complexities, but what does spending more than a year in space do to the human body? The record length for a single trip into space currently stands at 437 days. As impressive as that might be, prolonged periods in orbit can alter an astronaut's body in some surprising ways, including changing their muscles, brains, and even their gut bacteria.
So click on to learn more about the risks of spending too much time in space.