NASA's Perseverance rover captured an image on May 13, 2026, of a rock formation on Mars that appears to be a stack of three stones, resembling cairns used as trail markers on Earth. The image, taken on Sol 1,859 of the mission, was captured using the rover’s Mastcam-Z camera system in Jezero Crater, where Perseverance has been exploring since February 2021. While the formation sparks curiosity, scientists attribute it to natural geological processes rather than human or artificial intervention.

The most plausible explanation involves long-term wind erosion or the effects of ancient water flow, both of which have shaped Mars’s surface over billions of years. Data from NASA’s Curiosity rover supports wind as the dominant force in reshaping Martian terrain. The rock stack may in fact be a single formation that fractured and eroded into its current appearance, rather than separate rocks deliberately placed.

Perseverance has previously encountered other unusual geological features, including striped and sphere-studded rocks, each contributing to our understanding of Mars’s complex history. While some past images have fueled speculative interpretations — like the famous 'Face on Mars' from the 1976 Viking mission — researchers emphasize evidence-based analysis. This discovery adds to the growing picture of a planet once capable of supporting liquid water and, potentially, microbial life.