Scientists uncover new explanation for Mars’ red colour

Scientists have long believed that Mars’ red hue comes from hematite, a dry form of iron oxide. However, a new study suggests that a water-containing mineral called ferrihydrite may be responsible, reshaping our understanding of the planet’s history.

Using data from multiple Mars missions, researchers found that ferrihydrite, which forms in cool water, better matches the planet’s dust composition than hematite. This discovery implies that Mars rusted earlier than previously thought, during a time when liquid water was still present.

Published un Nature Communications, the findings suggest that Mars’ past environment may have been wetter than scientists believed, raising new questions about its habitability. The study also strengthens the case for retrieving Martian soil samples, as NASA’s Perseverance rover has already begun collecting material for future analysis on Earth.