Part 3/13:
Science shows that the physiological effects of microgravity begin well before landing on Mars, during the months-long voyage in orbit. In microgravity, the human body floats weightlessly, which sounds appealing but triggers a series of detrimental changes. Since humans evolved under Earth’s constant gravitational pull, our bodies are finely tuned to that environment.
Microgravity and Its Detrimental Effects
The absence of gravity causes a redistribution of bodily fluids. Fluids that are normally dispersed throughout our bodies migrate upward towards the head, creating pressure on the brain and eyes. This leads to vision problems and persistent headaches, with some astronauts experiencing permanent vision damage—a phenomenon science is still trying to fully understand.