NASA\u2019s Curiosity Mars rover discovered these bumpy, pea-sized nodules while exploring a region filled with\u00a0boxwork formations \u2014 low ridges standing roughly 3 to 6 feet (1 to 2 meters) tall with sandy hollows in-between. This mosaic is made up of 50 individual images taken by Curiosity\u2019s Mars Hand Lens Imager (MAHLI), a camera on the end of the rover\u2019s robotic arm, on Aug. 21, 2025, the 4,636th Martian day, or sol, of the mission. Ten images at different focus settings were taken at each of five locations to produce a sharp mosaic. The images were stitched together after being sent back to Earth.<\/p>\n
Figure A is the same image with a small scale bar added to the right-hand side.<\/p>\n
Nodules like these have been seen many times before on the Red Planet, including by Curiosity. They were made by minerals left behind as water dried billions of years ago. Crisscrossing the surface for miles, the boxwork formations suggest ancient groundwater flowed on this part of the Red Planet later than expected, raising new questions about how long microbial life could have survived on Mars billions of years ago, before rivers and lakes dried up.<\/p>\n
The boxwork ridgetops often include a dark line the team refers to as \u201ccentral fractures,\u201d where groundwater originally seeped through a rock crack, allowing minerals to concentrate. Surprisingly, the mission did not find nodules near these central fractures. Instead, they were found along the walls of the ridges and in the hollows between them. The wavy ridges between the groups of nodules are mineral veins made of calcium sulfate, also deposited by groundwater.<\/p>\n
Curiosity was built by NASA\u2019s Jet Propulsion Laboratory, which is managed by Caltech in Pasadena, California. JPL leads the mission on behalf of NASA\u2019s Science Mission Directorate in Washington as part of NASA\u2019s Mars Exploration Program portfolio. MAHLI was built by Malin Space Science Systems in San Diego.<\/p>\n
To learn more about Curiosity, visit:<\/p>\n