Scientists have spent millennia trying to figure out why Mars is red. Today, there is little doubt that the dust on the surface of the Red Planet contains a lot of iron oxides, which have a characteristic red tint. But there are many iron oxides, and some of them could only have formed if Mars had been potentially suitable for biological life in the past. The answer to one question may be the key to another.
Image source: AI generation Grok 3/3DNews
Unfortunately, until samples are returned to Earth from Mars for laboratory analysis, scientists cannot speak with 100% certainty about the composition of Martian dust. NASA is having difficulty implementing a program to return samples to Earth. This mission will probably be completed by the end of the 2030s. Chinese scientists may be ahead of NASA by five to seven years: they are actively developing technologies for collecting and delivering Martian soil in order to complete this historic mission by 2035. In the meantime, Martian soil samples are unavailable, researchers are studying spectral data, modeling processes, and recreating Martian conditions in laboratories.
Thus, a group of American scientists collected all available data from NASA and ESA orbiters, as well as information obtained by NASA rovers. The researchers were interested in everything related to the analysis of the surface of the Red Planet. In the laboratory, conditions were reproduced as close as possible to those on Mars. Scientists studied the possibility of the formation of iron oxides such as ferrihydrites on the surface of the planet. These compounds are formed at relatively low temperatures, in the presence of oxygen and liquid water. In other words, they can arise in conditions potentially suitable for the origin of biological life.
«The fundamental question of why Mars is red has been debated for hundreds, if not thousands, of years, the researchers explain. “Based on our analysis, we believe that ferrihydrite is present throughout the dust, and likely in the rocks as well. We are not the first to consider ferrihydrite as the cause of Mars’ red color, but we can now test this hypothesis in more detail using observational data and new laboratory techniques that allow us to recreate Martian dust in Earth conditions.”
«These new findings point to potential past habitability on Mars and highlight the importance of coordinated research by NASA and its international partners. Such research helps answer fundamental questions about our solar system and the future of space exploration,” the scientists conclude.