According to NASA “The most dangerous aspect of traveling to Mars is space radiation.” “On the space station, astronauts receive over ten times the radiation than what’s naturally occurring on Earth.” The problem is that you are exposed to radiation and it can make you sick. Earth has a protective shield and without it can cause cancer. My model is a pair of glasses. During the day you can walk around the spaceship wearing those glasses. I call them radiation spectacles. They are made out of plastic. They can be recycled.