Deep space radiation damages the heart and immune system

Researchers at the Medical College of Wisconsin simulated a Mars mission in rats: a 1.5 Gray radiation dose caused perivascular fibrosis around coronary vessels, with scar tissue doubling after 270 days. Microgravity alone barely affected the heart, but combined with radiation it suppressed immunity and triggered CHIP-linked mutations.

• A 1.5 Gray dose caused coronary fibrosis; scar tissue doubled after 270 days
• At a three-year Mars mission dose, 83% of rats developed fibrosis within a year
• Spleens lost two-thirds of Natural Killer cells that target cancer cells
• Permanent mutations tied to CHIP and leukemia risk appeared 235 days after exposure