NASA's Curiosity Rover Captures Stunning Images Of Mysterious Martian Spiderwebs

by Aaron Leong — Tuesday, February 24, 2026, 11:38 AM EDT

NASA’s Curiosity rover has finally completed its focused survey of the so-called spiderwebs of Mars, providing us the first close-up look at a massive network of geologic ridges on Mount Sharp that have puzzled scientists since they were first spotted from orbit years ago.

curiosity boxwork wide — *Curiosity rover captured this panorama of boxwork formations—the low ridges seen here with hollows in between them— using its Mastcam on Sept. 26, 2025. (Credit: NASA/JPL-Caltech/MSSS)*

Stretching for miles across the slopes of the mountain, these boxwork formations consist of intersecting ridges that stand between three and six feet tall. Viewed from space, they resemble a giant web draped over the Martian floor. (By the way, getting to this location is nothing to sneeze at. Let's not forget, Curiosity has already been journeying for 13 years through the Gale Crater, with the last six months of that time navigating the difficult terrain to reach the boxworks.)

The ridges aren't just interesting to look at, but also serve as fossilized records of a time when liquid water was still active on the planet, long after many researchers believed the surface had become a frozen wasteland. Billions of years ago, groundwater seeped through deep fractures in the Martian bedrock.

As this water flowed, it deposited minerals that eventually hardened into a concrete-like substance. Over time, the surrounding softer rock was scoured away by winds, leaving behind the reinforced mineral veins as a standing lattice of ridges. The rover's Mastcam and robotic arm have spent months documenting these central fractures, which appear as dark lines running through the heart of the ridges, confirming the hypothesis that they were once the primary conduits for ancient water.

boxwork top — *These pea-sized nodules were formed by minerals left behind as groundwater was drying out on Mars billions of years ago. (Credit: NASA/JPL-Caltech/MSSS)*

What has surprised the mission team is the discovery of nodules, little pea-sized, bumpy mineral clusters scattered along the ridge walls and the sandy hollows between them. While nodules are a common sign of past water on Mars, their placement here is unusual: they aren't concentrated at the central fractures where the water was most active but are instead distributed in the surrounding areas. Although the team isn't certain of the cause yet, the nodule location could mean a history of fluctuating water levels, where the ridges may have formed first, followed by later episodes of groundwater that left these mineral beads behind.

Furthermore, analysis by the rover's internal laboratory has revealed the presence of clay minerals within the ridges and carbonates in the hollows. The presence of these minerals, particularly when found so high up Mount Sharp, indicates that the groundwater table was much higher and remained stable for a longer period than previously estimated. If salty, liquid water was indeed flowing through these cracks while the rest of the planet was drying out, it could have provided a shielded, temperate environment where microbial life might have made its last stand.

Curiosity rover is expected to leave the boxwork formation behind in March.