New Delhi, Feb 26: A recent study suggests that Mars' distinct red hue may be attributed to ferrihydrite, an iron-containing mineral that forms in the presence of cool water, indicating the planet may have once supported habitable conditions. The findings, published in Nature Communications, challenge previous assumptions about Mars' mineral composition and its environmental history.
The research highlights that dust on Mars consists of various minerals, including iron oxides. Among them, ferrihydrite is now considered a likely contributor to the planet's red coloration. "We’re not the first to propose ferrihydrite as a reason for Mars' red color, but we now have stronger evidence through observational data and laboratory simulations," said lead author Adam Valantinas, a postdoctoral fellow at Brown University, USA.
Unlike hematite, another iron oxide previously believed to be responsible for Mars' coloration, ferrihydrite forms at lower temperatures and requires the presence of cool water. This discovery suggests that Mars may have had a more hospitable environment in its past, possibly supporting liquid water.
Mars is thought to have transitioned from a wet to a dry planet billions of years ago as its atmosphere was stripped away by solar winds. The planet’s weak magnetic field, caused by the cooling of its core, left it vulnerable to these solar forces, ultimately resulting in its current dry and cold state.
The study analyzed data from multiple Mars missions conducted by NASA and the European Space Agency. Researchers also conducted laboratory experiments simulating Martian conditions to examine how light interacts with ferrihydrite and other minerals.
Further confirmation of the findings may come from NASA's Perseverance rover, which is currently collecting and analyzing Martian samples. The rover, launched in July 2020 and landed on Mars in February 2021, aims to uncover details about the planet’s ancient climate and chemical evolution.
“To understand Mars' past habitability, we need to examine the conditions present when these minerals formed," Valantinas explained. "Our study shows that ferrihydrite formation requires oxygen and water, reinforcing the possibility that Mars had a more Earth-like environment in its early history."
These findings add to growing evidence that Mars once harbored conditions suitable for liquid water, bringing scientists closer to answering the long-standing question of whether the Red Planet was ever capable of supporting life.