For decades, scientists studying the Martian surface have relied primarily on models that treat the planet as relatively flat. These models have helped explain daily and seasonal temperature changes but often overlook a crucial fact: Mars is not flat.
New 3D Model Developed by ISRO's PRL
A team of researchers from the Indian Space Research Organisation's Physical Research Laboratory has developed a detailed three-dimensional model of the Martian surface that simulates temperature variations across real landscapes, including craters, slopes, ridges, and depressions. The study was published in the journal Monthly Notices of the Royal Astronomical Society.
The researchers—K Samadhanam Raju, K Durga Prasad, Ambily G, P Kalyan Reddy, Varun Sheel, and Anil Bhardwaj—state that the model provides a more realistic picture of heat movement across and beneath the Martian surface. This information could prove valuable for future robotic and human missions.
Limitations of Traditional Models
Traditional models, including the widely used KRC thermal model, primarily calculate heat moving vertically through the soil. While they successfully reproduce average day-night temperature changes, they cannot account for how neighboring slopes may warm or cool differently based on their orientation to the Sun.
The new model employs high-resolution digital terrain maps and finite-element simulations to recreate Mars in three dimensions. This enables scientists to calculate how sunlight, shadows, surface roughness, and lateral heat flow affect temperatures at local scales.
Validation and Accuracy
To test accuracy, the team first compared the model with the established KRC framework, finding strong agreement in reproducing the overall daily temperature cycle on Mars. They then validated it using actual measurements from NASA's InSight lander, which operated on Mars from 2018 to 2022. The simulations closely matched observed temperatures, including daytime highs and cold nighttime conditions.
The model was also applied to a region within Jezero Crater, where NASA's Perseverance rover is exploring an ancient river delta. Here, the advantages of the three-dimensional approach became clearer. While conventional models provide a single average temperature for an area, the new simulations revealed significant temperature differences over short distances. Sun-facing slopes became much warmer than shaded terrain, with differences of up to 20-30 Kelvin.
Implications for Martian Science
Such variations matter because temperature differences create pressure differences in the thin Martian atmosphere. These can generate local winds and contribute to dust lifting, a key process behind Mars' famous dust storms. According to the researchers, existing one-dimensional models cannot capture these local effects because they assume the surface behaves uniformly.
The findings could help scientists better interpret rover observations, assess future landing sites, and understand interactions between the Martian surface and atmosphere. The model may also assist in planning future human habitats on Mars, where predicting local thermal conditions will be essential for safety and engineering design.
Conclusion
The researchers conclude that Mars is far more thermally diverse than simple models suggest. By accounting for the planet's real topography, the new framework offers a closer look at the environmental conditions that future explorers, both robotic and human, are likely to encounter.
