NASA's Curiosity Spots Mysterious Mars Pits on Mount Sharp

NASA's Curiosity rover has found something on Mars that its science team says it has never seen before. Scattered across the bedrock of Mount Sharp are broad, shallow pits that look, at a glance, like footprints pressed into stone. The formations turned up during a week of work in late August 2026, and these Mars pits do not match any of the surface marks recorded in nearly 14 years of exploring the Red Planet.

The rover photographed the pits on Mount Sharp, the mountain that dominates the floor of Gale Crater, where Curiosity has been climbing for years. Each pit is about a centimetre wide, far broader and shallower than the small voids the rover usually records. Michelle Minitti, deputy principal investigator for Curiosity's Mars Hand Lens Imager (MAHLI), wrote in a mission update published on 3 September 2026 that the formations were unlike anything the mission had seen in the past. They appeared across two of the rover's work areas during that week, according to the update.

These are not actual footprints. Small pits and divots are common in Martian bedrock: when hard nodules or pebbles weather out of their host rock, they leave a void behind, a process the Curiosity team has documented for years. What sets these Mars pits apart is their geometry. Minitti said they were "much broader and shallower than past features and were not accompanied by obvious objects that were once in the pits." Whatever once occupied the depressions left nothing behind to identify itself.

What the instruments found inside the pits

The team studied the strange marks with the rover's cameras and science instruments before driving on, including MAHLI, the Mastcam cameras, the ChemCam instrument and the Alpha Particle X-Ray Spectrometer (APXS), reported by Space.com. The close-up images revealed complex layers of Martian regolith inside the pits, with different textures and structures from the surrounding rock.

The chemistry was the bigger surprise. The layered material inside the pits appears chemically different from the main bedrock around it, according to BBC Sky at Night Magazine, which first explained the find from Minitti's mission blog. That chemical difference suggests the pits hold a record of processes that shaped this part of Mount Sharp's layered rocks, a story the team has not read before. The rover captured the now-famous image of one pit at 07:59:21 UTC on 19 August 2026, and researchers are still working through what the data means. The photograph drew wider attention when Space.com featured it as the space photo of the day for 15 September 2026, and the BBC's Sky at Night Magazine, PetaPixel and UNILAD picked up the story within days of the mission update.

"They were a welcome new puzzle into the processes that have affected this particular section of rocks in the stratigraphy of Mount Sharp," Minitti wrote. Curiosity landed in Gale Crater in August 2012 and has since crossed a dry lakebed, climbed high up Mount Sharp, and built one of the most detailed geological records ever gathered on another planet. A mission this old is not supposed to surprise its team. After nearly 14 years of operation, the rover keeps finding features it cannot immediately explain.

Why a few centimetres of rock matter

Mars science now turns on small details. The question of whether water once persisted long enough to support life is being answered grain by grain, and shallow pits like these can hold clues. Layers with different chemistry inside a pit can show how minerals were deposited, dissolved or altered, and each of those processes says something about the water and climate of ancient Mars.

The pits also show how much remains unknown on a planet that has been mapped in detail. Orbital cameras can photograph features metres across, but only a rover can examine a centimetre of rock up close and read the chemistry inside. The mission team has not announced a conclusion about how the Mars pits formed. Curiosity remains in good health after nearly 14 years, and its work on Mount Sharp continues. For more detail on the discovery, see NASA's Curiosity mission page, the mission reporting at BBC Sky at Night Magazine, and the original coverage at The Daily Galaxy.

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