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Engineering

Selecting Radiation Shielding Materials for Crewed Martian Surface Habitats

Quick fact

On Mars, a habitat shielded by 1 meter of regolith (the loose rock and dust on the surface) can reduce the annual radiation dose from galactic cosmic rays by roughly 50% compared to an unshielded habitat, but the exact amount varies with solar activity and regolith composition.

Why this is interesting

You might think a thick slab of lead would be the best shield against space radiation. But on Mars, engineers are considering using dirt, water, and even plastic—why?