What's different about our health in space? Former NASA astronaut Mike Massimino breaks down all the differences between how we take care of ourselves on Earth and in space. What happens to your body if you don't work out? What do you do if you need to vomit? What happens to your bones when you get back to Earth?

Mike Massimino is a former NASA astronaut, senior advisor for space programs at the Intrepid Museum, and professor at Columbia University.