Mars Gullies Carved by Moving Dry Ice, Study Finds

Utrecht University research reveals that moving blocks of CO₂ ice, not liquid water, carved Mars' mysterious gullies, reshaping our understanding of the planet's geology.

A groundbreaking study from Utrecht University has solved a decades-old Martian mystery: the enigmatic gullies scarring the planet's slopes were likely carved by sliding blocks of dry ice, not by liquid water. This discovery, leveraging advanced orbital imagery and climate modeling, fundamentally rewrites the narrative of recent geological activity on Mars. It dispels long-held theories that these features were evidence of fleeting liquid water, thereby dramatically lowering the probability of near-surface habitability in these regions. This paradigm shift immediately impacts the strategic objectives of space agencies and private explorers, forcing a recalibration of where to search for signs of past life and how to assess landscape risks for future rovers and human missions.

This research delivers a definitive verdict where previous planetary scienace relied on ambiguous terrestrial analogs. While past missions collected orbital data, it was the novel geological analysis from Utrecht that connected the dots, proving that the Martian climate permits this unique process. The study's power lies in its elegant simplicity it doesn't invent a new hydrology but applies the planet's own atmospheric conditions and known CO₂ cycles as the primary sculpting tools. This matters because it showcases how re-examining existing data with a fresh, physics-based perspective can solve mysteries that have persisted for years, delivering more certainty than any incremental probe could achieve alone.

For mission planners at NASA and emerging private space entities, this is a pivotal operational insight. The planetary geology of candidate landing sites must now be re-evaluated through this new lens, prioritizing stability over the false allure of ancient water signs. The forward-looking implication is profound: our understanding of surface processes in other arid worlds must expand. The next cycle of interplanetary exploration will be guided by this discovery, focusing on truly active, dry geological processes and leveraging this knowledge to de-risk the ambitious human exploration of the Martian surface, ensuring that our first footprints are placed on solid, predictable ground.