Mars has long fascinated observers with its striking red hue. New research from multiple space agencies suggests that iron in the planet’s rocks is primarily responsible for this distinctive color. However, scientists still don’t fully understand why the surface appears red.
A new study by Adomas Valantinas, a postdoctoral researcher at Brown University, sheds light on Mars’s earliest environment and its potential habitability. Valantinas and his team compared data from multiple spacecraft and tested basalt mixtures with various iron oxides in the lab.
The research points to ferrihydrite, a water-rich iron mineral that can only form in the presence of cool liquid water. This finding suggests that Mars may have had a cooler and more moist environment earlier than previously thought. The team discovered that ferrihydrite combined with basalt replicated Martian dust more convincingly than other mixes.
The discovery implies that Mars was once very different from its current dry, cold state. Past rover missions found signs of ancient streams and lakes, but the planet’s thin atmosphere now makes liquid water on its surface improbable for long stretches.
The presence of ferrihydrite indicates that water likely existed on Mars when the mineral first formed. Many experts believe that liquid conditions faded away several billion years ago as Mars lost much of its atmospheric protection. The NASA-ESA Mars Sample Return program aims to gather Martian rocks, dust, and regolith for deeper inspection on Earth.
This latest finding strengthens the argument that early Mars had conditions suitable for life. Understanding these iron minerals unlocks a chapter in Mars’s history that researchers are just beginning to unravel.
Source: https://www.earth.com/news/why-is-mars-red-scientists-think-they-figured-out-billion-year-old-mystery