<ul><li>The characteristic red hue of Mars may be due to ferrihydrite instead of rusted iron minerals, as previously believed.</li><li>New research suggests that Mars' red color is better matched by ferrihydrite, an iron oxide that contains water.</li><li>This indicates that Mars may have been a cool ocean world in the past, challenging the assumption that it turned red after losing its water.</li><li>Further research is needed to determine the original source of ferrihydrite and its timing and composition in Mars' history.</li></ul>

Scientists made fake Martian dust — and found a big surprise about what makes Mars red

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