3. Galactic Cosmic Rays (GCRs) Are Ubiquitous
Galactic cosmic rays (GCRs) are high-energy particles originating from distant supernovae and other cosmic events outside our solar system. On Mars, these rays relentlessly penetrate the thin atmosphere and unshielded surface, delivering a steady dose of radiation year-round. NASA’s Mars radiation studies highlight GCRs as one of the most persistent and challenging risks for both robotic and future human missions.