NASA’s Curiosity rover has just unveiled its first close-up images of a bizarre and fascinating feature on Mars – large, web-like structures that resemble giant spiderwebs. These unusual formations, known as “boxwork,” have sparked intrigue among scientists due to their potential to reveal important details about the planet’s past, particularly regarding the presence of water and the possibility of extraterrestrial life.

What Are Martian ‘Spiderwebs’?

The boxwork formations, which span up to 12 miles (20 kilometers), are comprised of mineral-rich ridges that intersect in a criss-cross pattern. When viewed from above, they bear an uncanny resemblance to the webs spun by spiders, hence their name. The features are part of a larger geological structure found on the slopes of Mount Sharp, located in the heart of Gale Crater, where the Curiosity rover has been exploring since 2012. These striking formations were formed by ancient groundwater that passed through the region, leaving behind mineral deposits that hardened over time.

Until now, scientists have only been able to study these formations from afar, using satellite imagery. But thanks to Curiosity’s recent findings, researchers now have a closer look at the structures and are eager to understand what they might reveal about Mars’ history.

A Closer Look at the Geological Formation Process

Curiosity’s team believes that the ridges of boxwork were formed through a process involving groundwater that seeped through cracks and fissures in the rock. This groundwater left behind minerals that accumulated and hardened into cement-like deposits. Over millions of years, the Martian winds slowly eroded the surrounding rock, but the mineral deposits remained intact, eventually forming these intricate ridges.

On Earth, smaller versions of boxwork can be found on cave walls, where they form in a similar way to stalagmites and stalactites. These formations often serve as important clues about the past environmental conditions of Earth’s caves. Now, with Mars offering a much larger scale of these features, scientists are hopeful that they will help unlock the mystery of the planet’s watery past and its potential to support life.

Exploring an area previously only seen from orbit, the Curiosity rover has found dramatic new evidence of ancient groundwater. The rover is using its drill to snag samples of rock that will give geologists new clues to how this area formed. https://t.co/2qQR169QeE pic.twitter.com/zZJzaMwW8H — NASA Mars (@NASAMars) June 23, 2025

Unexpected Mineral Discovery

Along with these first-ever close-up images, Curiosity also drilled into rocks surrounding the boxwork formations to gather samples for analysis. The rover discovered veins of calcium sulfate, a salty mineral typically left behind by groundwater. What makes this find particularly exciting is that this mineral has never been observed so high up on Mount Sharp before.

“This particular mineral hasn’t been seen so far up Mount Sharp before, so its discovery here is really surprising,” said Abigail Fraeman, Curiosity’s deputy project scientist at NASA’s Jet Propulsion Laboratory. The presence of calcium sulfate provides further evidence that liquid water once flowed through this area, which could have been a critical factor for the planet’s habitability in the distant past.

Studying the Past to Understand Mars’ Potential for Life

The team behind the Curiosity mission is particularly interested in these boxwork features because they could help answer some of the fundamental questions about Mars’ ability to support life. The minerals trapped within the ridges are believed to have crystallized underground, where conditions may have been warmer and where salty liquid water could have flowed.

These conditions are not entirely unlike those believed to have existed on early Earth, where microbes may have survived in a similar environment. “Early Earth microbes could have survived in a similar environment. That makes this an exciting place to explore,” said Kirsten Siebach, a Curiosity mission scientist at Rice University.

By studying the boxwork formations, scientists hope to gain valuable insights into the possibility that Mars may have once harbored life, or could still harbor microbial life in some form today. The findings from Curiosity could prove crucial in understanding whether Mars was ever habitable, and what the planet’s current conditions mean for future exploration.

For now, researchers remain focused on analyzing the boxwork formations and their surrounding mineral deposits, hoping to uncover more clues about Mars’ fascinating history and its potential to support life in the past or even the future.