“During such interplanetary travel, astronauts will be exposed to multiple sources of ionizing radiation, including galactic cosmic rays, solar particle events, and trapped radiation in the Van Allen belts,” claims the paper. For this reason, humans are going to need serious protection to not only survive the long journey to Mars but to also become a fully space-faring civilization that continues to extend our reach into the solar system.

Source: Space Radiation Devastated the Lives of Apollo Astronauts | Observer