Space tourism is here and will, according to global firm UBS, be a $900 billion industry by 2030. Space travel actually changes what the human brain looks like and how it works. Science researchers, including myself, have observed negative changes in astronauts' brain areas involved in reasoning, decision-making, memory, and vision. With space travel exponentially increasing over the next decades, we need to be concerned about the effects of space on tourists’ brains, too. We'll discuss the cost of space travel on the brain and what it means for space exploration to Mars and space tourism.