What chemical alteration did high-energy radiation cause on the Martian surface after the atmosphere thinned?

Answer

It altered surface rocks by interacting with remaining oxygen and hydroxyl radicals, making the soil less hospitable

The prolonged exposure of the dried-out surface to high-energy cosmic radiation and solar ultraviolet light caused significant chemical changes beyond simple mass loss. When water vapor broke down, the reactive components left behind, specifically oxygen and hydroxyl radicals, vigorously interacted with the surface minerals. This process chemically altered the surface rocks, saturating them with oxidized compounds, which may make the soil structurally resistant to holding or absorbing liquid water in a stable, large-scale manner, even if pressure were restored.

What chemical alteration did high-energy radiation cause on the Martian surface after the atmosphere thinned?
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