Mars rover narrows search for boxwork mystery after 13 years

Curiosity has been exploring the same patch of Martian ground for over a decade, and this week, the science team finally decided where to dig.

Thirteen years ago, before Curiosity touched down on Mars, researchers mapped out the geologic features they wanted to study on Mount Sharp's slopes. They found valleys, river channels, lakebeds — and something unexpected: boxworks. These are expansive networks of ridges and hollows, like a geological maze carved into the bedrock. For years, the team watched from a distance. Now they're close enough to solve what created them.

Since Sol 4600 (that's Martian day 4600 since landing), Curiosity has been methodically mapping the boxworks, running every instrument it carries across the ridges and into the hollows. The rover's chemistry tools analyzed rock samples from the center of ridges to their edges, looking for clues about what holds them together and makes them rise higher than the surrounding hollows. Cameras mapped the architecture in detail. Other instruments measured water content and grain size variations, building a three-dimensional picture of how this landscape was formed.

It's detective work, but patient. Each stop along the route was another data point. Each instrument reading another clue.

This week, the team reviewed all those results and made their move. Curiosity will head north to a hollow called "Monte Grande," where the bedrock looks promising for drilling. Once there, the rover's SAM instrument — essentially a chemistry lab on wheels — will analyze samples from both the ridges and hollows. Comparing their mineral composition, water content, and organic chemistry should finally reveal how the boxworks formed.

Why this matters: Understanding how these features formed tells us something about Mars's past climate and water history. The boxworks might be evidence of ancient groundwater, or they might reveal how Martian rock responds to weathering over billions of years. Either way, it's another piece of the puzzle about whether Mars could have once supported life.

Curiosity's other instruments kept working too. Weather sensors tracked dust in the atmosphere and watched for dust devils. The radiation detector continued its steady monitoring of space weather. Even after 13 years, the rover is still gathering data on multiple fronts.

The drill site decision marks the beginning of the next phase. A ridge drilling will come later, but for now, Monte Grande is the target. Two samples — one from a hollow, one from a ridge — should answer a question that's been waiting 13 years for an answer.