When the La Pérouse A impact excavated material from the side of a hill of highland material (1.5 to 2 km taller than the plains to the west), the slope became unstable and collapsed into the crater La Pérouse A. The result is a crater with one rim 920 meters higher than the other. The Featured Image shows the top of this landslide, now the new rim of La Pérouse A. The landslide material inside the rim is high reflectance, while the undisturbed section of the highland material is relatively darker. Despite being the same composition, the landslide material is higher reflectance since it is fresh (recently uncovered). Faint lines along the outer edge of the rim are evidence of highland material slumping towards the crater. Collapse features on the Moon often display slump lines, which show where material has fractured and moved downwards, but not completely collapsed. Subsequent impacts or seismic shaking could cause further landslides inside the crater!
Explore the entire NAC mosaic of the crater La Pérouse A below!
Posted by Sarah Braden on September 20, 2012 08:00 UTC.