Original title: Current water trapping micro-habitats on the surface of Mars
Anna Bognar, Bernadett D. Pal, Akos Kereszturi · September 2026
Any liquid water on the surface of Mars dries up fast during the day, making it hard for life to survive. Researchers built a model to see how water could stick around. Salts on the Martian surface pull moisture from nighttime air to create tiny amounts of liquid. As temperatures change between day and night, salt crystals shrink and expand, opening and closing microscopic cracks. At night, liquid water seeps into these open cracks. When daytime warms the ground, the crystals expand, partially pinching the cracks shut. This traps the liquid inside and stops it from evaporating right away. Just two to three millimeters inside, microbes could stay damp, get protection from harsh ultraviolet rays, and still collect visible light for photosynthesis.
Imagine a sponge that soaks up water at night but dries out as soon as the sun hits it. If the sponge had tiny pockets that could close up when it gets warm, the water inside those pockets would stay wet even while the rest dries. Here, salt crystals on Mars act like that sponge: at night they absorb moisture and fill their internal cracks, then during the day the cracks shrink, trapping the liquid inside and protecting it from evaporation.
If this mechanism works, it means liquid water could exist temporarily near the surface of Mars today, not just in the distant past. That changes where we search for signs of life and how we think about Mars' current habitability. Future missions might target these salt-rich regions to look for microbial life.
This is a conceptual feasibility analysis, not an experimental demonstration. The model assumes specific salt distributions and thermal cycles that have not been directly observed on Mars. The trapping mechanism relies on micro-cracks that may not exist in the required form. The analysis is limited to one region (Acidalia Planitia) and one season (100-130 sols per year). Actual liquid water persistence and habitability remain unconfirmed.
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Current water trapping micro-habitats on the surface of Mars — Anna Bognar, Bernadett D. Pal, Akos Kereszturi
Abstract licence: CC0
Explanation generated by Synthesis from the abstract — it is not the original paper. This is a preprint, so it hasn't necessarily been peer reviewed.