BENGALURU: For decades, scientists trying to understand the Martian surface have relied largely on models that treat the planet as if it were relatively flat. These models have helped explain how temperatures change through the day and across seasons, but they often miss something important: Mars is not flat.A team of researchers from Isro’s Physical Research Laboratory (PRL) has now developed a detailed 3D model of the Martian surface that can simulate how temperatures vary across real landscapes filled with craters, slopes, ridges and depressions. The work has been 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 — say the model provides a more realistic picture of how heat moves across and beneath the Martian surface, information that could prove valuable for future robotic and human missions.Traditional models, including the widely used KRC thermal model, mainly calculate heat moving vertically through the soil. While these approaches successfully reproduce average day-night temperature changes, they cannot account for how neighbouring slopes may warm or cool differently depending on their orientation to the Sun.The new model uses high-resolution digital terrain maps and finite-element simulations to recreate Mars in three dimensions. This allows scientists to calculate how sunlight, shadows, surface roughness and lateral heat flow affect temperatures at local scales.To test its accuracy, the team first compared the model with the established KRC framework. The two showed strong agreement in reproducing the overall daily temperature cycle on Mars. The researchers then validated the model using actual measurements from Nasa’s InSight lander, which operated on Mars between 2018 and 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 that temperatures can differ significantly over short distances. Sun-facing slopes became much warmer than shaded terrain, producing differences of up to 20-30 Kelvin.Such variations matter because temperature differences create pressure differences in the thin Martian atmosphere. These can generate local winds and contribute to dust lifting, one of the key processes 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.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.
