Geology of Atlas crater, the prime landing site of the Emirates Lunar Mission Rashid-1 rover

Located at 46.7°N, 44.5°E, Atlas is a well-known floor-fractured impact crater which records a complex volcanic history. Emplaced ~3.82 Gy ago within the lunar highlands, the 87 km diameter crater is characterized by the presence of collapsed walls, a rough and undulated floor marked with fractures, a ~1 km central peak complex, and two pyroclastic deposits. The evolution of Atlas crater is related to those of a nearby ~1.1 km high unnamed dome and of the Hercules impact crater, dated at 3.71 Gy. Cratering equations and rheological models were used to specify some aspects of the crater’s geologic history. Atlas crater tapped into a pluton at a depth <13.5 km, dominated by mixed plagioclase, pyroxene and spinel VNIR signatures, and was later intruded by magma that stalled at ~2 km depth. Atlas crater lies in the center of a regional thermophysical anomaly measured in Diviner dataset, suggesting compositional or textural anomalies in the subsurface. The unnamed dome, emplaced by lavas as viscous as those forming known lunar silicic domes, could provide clues to this anomaly, as it may evidence the presence of more evolved alkalic or silicic rocks in the area. In addition, telescopic photometry and spectropolarimetry highlight the presence of more densely packed and either larger and/or rougher regolith grains in the pyroclastic deposits. Because of its high scientific value, Atlas was selected as the prime landing site of the Emirates Lunar Mission Rashid-1 rover, which made a hard landing on the Moon in April 2023.