University of Sydney researchers create first global Martian soil map

Researchers at the University of Sydney have developed the first global classification system and map of Martian soils, covering approximately 92% of the planet's surface. The study, published in the journal CATENA, utilizes orbital observations and planetary models to categorize nearly 800 million individual locations into 2,000 distinct soil types.

The new framework, named the Provisional Polythetic Areth Classification System (PPACS), introduces the term ‘areths’—derived from Ares, the Greek name for Mars—to describe these soil classes. The system organizes soil properties into a three-tier hierarchy consisting of 10 major realms, 100 assemblages, and 2,000 terminal forms based on texture, mineralogy, pH, and profile thickness.

Led by PhD candidate Daniel Irving and Professor Alex McBratney, the team also developed a scoring system to evaluate the viability of these soils for future greenhouse agriculture. The evaluation considers five critical factors: water retention capacity, pH levels, profile thickness, clay content, and gravel proportion. This data is intended to help future colonists and researchers identify optimal locations for establishing life-support systems and agricultural bases on Mars.