Martian Gullies Rewritten: CO2 Ice, Not Water, Likely Carved the Terrain
A new arXiv preprint analyzing Mars Express and MRO data suggests Martian gullies aren’t carved by liquid water—and CO2 geysers aren’t the culprit either. The authors favor CO2-ice–driven sublimation or avalanche-like flows during the late stages of seasonal ice loss, based on a lack of spectral water signals and a timing mismatch with geyser activity, though the work remains a preprint not yet peer-reviewed.
