Picture a vast field of honeycombed polygonal rocks stretching to the horizon in an otherworldly valley. NASA’s Curiosity rover did, and the Valle Grande, as NASA’s Jet Propulsion Laboratory is calling it, is the latest fascinating spot to be imaged by the rover, now in its 13th year of trundling across the Martian landscape. The rover has seen small patches these fractures before, NASA reports, but never at this scale.
In a 360-degree panorama that the rover captured on June 19 and 20, the 4,930th and 4,931st Martian days, or sols, of the mission, the polygonal shapes spread in all directions for as far as the rover can see. They even wrap around the sides of a nearby butte nicknamed “Miraflores,” which stands 20 feet (6 meters) tall and is topped with a thick cap of sand.
“We’ve seen a lot of fascinating landscapes through Curiosity’s eyes, but this sea of polygons took our breath away,” said project scientist Ashwin Vasavada of JPL. “We measured their shapes and chemistry carefully and are hopeful there are clues in the data as to how these features formed.” Possibilities include ancient mud cracking, freezing and thawing, or water being squeezed out the rock by compression. (Sorry, Marvin‘s not on the list)
Polygonal fractures record the ancient history of Martian sediment, when lakes and streams covered the lower foothills of Mount Sharp, the mountain Curiosity has been climbing for more than a decade. Astrobiologists are interested in the chemistry there and hope to detect signs similar to those present on Earth; last year the rover detected the largest organic molecules yet found on Mars. From the press release:
The rover has previously uncovered chemistry left over from Mars’ watery history, including carbon-based molecules believed to be precursors to RNA and DNA, two nucleic acids that carry genetic information. Scientists have no way of knowing whether these organic molecules were created by biologic or geologic processes — either path is possible — but their discovery reconfirmed that ancient Mars had the right chemistry to support life.
In 2023, Curiosity surprised scientists with its first glimpse of the hexagonal patterns, then cracked open a rock to find pure sulfur crystals for the first time on Mars.
NASA’s Curiosity Mars Rover Discovers Field of Honeycomb Textures [NASA]
NASA’s Curiosity Discovers a Field of Martian Polygons [NASA]
