Scientists have reevaluated the reason behind Mars’ iconic rusty red color, finding that it formed much earlier than previously thought due to liquid water present on the planet’s surface. A study combining European Space Agency (ESA) and NASA spacecraft data with new laboratory experiments on replica Mars dust reveals that ferrihydrite, an iron oxide containing water, is the most likely culprit.
Mars’ red hue has been attributed to rusted iron minerals in the dust for decades, but researchers had initially concluded that this type of iron oxide must be formed under dry surface conditions. However, new analysis suggests that Mars’ rusty material was created when liquid water still existed on the planet’s surface, rewriting our understanding of the Red Planet’s history.
The study used advanced laboratory techniques to create a replica of Martian dust and compared it with data from orbiting spacecraft. The results show that ferrihydrite is the best match for the minerals detected by NASA’s Mars Reconnaissance Orbiter, the ESA’s Trace Gas Orbiter, and other missions.
This breakthrough implies that Mars rusted earlier than previously thought and that the planet may have had a more hospitable environment in its past. The discovery also opens up new possibilities for understanding the possibility of life on Mars.
Source: https://www.esa.int/Science_Exploration/Space_Science/Mars_Express/Have_we_been_wrong_about_why_Mars_is_red