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Curiosity Blog, Sols 4941-4947: (Pin)Stripes on the Fourth of July
Written by Deborah Padgett, MSL Operations Product Ground System Task Lead at NASA’s Jet Propulsion Laboratory
Earth planning date: Thursday, July 2, 2026
Curiosity spent the week leading up to the Fourth of July holiday approaching a geologic boundary between a very smooth but somewhat sandy region and a rougher bedrock unit.
Leaving the polygonal terrain behind, the rover arrived at the first location of the week on Sol 4939 and, on the following sol, 4940, looked for dust devils with Navcam and performed an AEGIS ChemCam laser-spectroscopy observation and Mastcam imaging of a target selected onboard the rover. Unfortunately, there were no large rocks appropriate for brushing with the DRT at this rover stop.
On Sol 4941, the MAHLI camera imaged “Malpartida” and “Pico del Tunari,” which are both light-colored rock fragments, and APXS performed X-ray spectroscopy on them to determine their composition. ChemCam used active laser spectroscopy to zap the “Kunturiri” light-colored bedrock fragment, while “Mecoyita,” a dark-toned “float” rock, which appears to have been transported into this area from elsewhere, was observed passively. ChemCam also used its telescopic RMI camera to study sedimentary layers at the base of the Cordillera butte. Mastcam obtained several image mosaics on a ridge of sand and rock fragments dubbed “Sitajana.”
On the following sol, 4942, Mastcam continued its study of “Sitajana,” and ChemCam RMI obtained more views of Cordillera butte. Navcam took a suprahorizon cloud movie and dust-devil movie. Finally, ChemCam obtained laser spectroscopy of the dark bedrock fragment “Toconce” with documentation imagery from Mastcam. Mastcam also imaged “Sierra Vicuña Mackenna” to study a partially uncovered rock shedding sand in an area of small dune ripples.
On the afternoon of Sol 4942, Curiosity drove about 36 feet (about 11 meters) to the edge of the geologic contact and took post-drive panoramic mosaics with Navcam and Mastcam. These images revealed a field of exposed bedrock outcrops with beautiful pinstriped layers. A Navcam AEGIS observation was taken for onboard selection of a ChemCam laser spectroscopy target. This soil and rock target was observed by ChemCam with Mastcam documentation on Sol 4943. In addition, Navcam performed a dust-devil movie, and Mastcam took an atmospheric dust observation.
For Sol 4944, two adjacent light bedrock targets “Laguna Fea” and “Laguna Lejia” were selected for DRT brushing, MAHLI imaging, and APXS X-ray spectroscopy to determine composition. ChemCam laser spectroscopy will target the darker ledge of bedrock “Hornillos,” with accompanying Mastcam documentation. The investigation of “Hornillos” will include detailed imaging by MAHLI, but it was determined to be too rough for DRT brushing. Mastcam will take a large mosaic of images on the field of striped bedrock outcrop “Cerro Castillo,” as well as a smaller mosaic of a nearby trough. The ChemCam telescopic RMI camera will target a dark layer on butte Cordillera, which appears to be shedding dark boulders. Navcam will take a dust-devil movie and suprahorizon cloud movie.
On Sol 4945, ChemCham will do laser spectroscopy of “Laguna Lejia” with Mastcam image documentation, and the ChemCam RMI telescopic camera will study another area at the base of butte Cordillera where the location of large stones on the slope suggests that ice processes may have played a role. A Navcam dust-devil survey and Mastcam dust-imaging study will also be done. In the afternoon, there will be a Navcam dust-devil survey, zenith observation, and suprahorizon cloud movie, as well as a Mastcam dust observation and 20×4 mosaic image of butte Mishe Mokwa. Overnight, there will be an APXS atmospheric observation lasting many hours.
During Sol 4945, ChemCam will perform laser spectroscopy of target “La Puntilla” with accompanying Mastcam imaging, followed by a ChemCam passive-sky observation. Curiosity will then drive about 56 feet (17 meters) towards a large, dark boulder in the distance, which may be a meteorite, and do post-drive imaging and Navcam sky flats.
On the following morning, there will be an atmospheric observation including a Navcam zenith movie, suprahorizon cloud movie, and line-of-sight dust observation, as well as a Mastcam dust “tau” observation.
