Evolution of a comet cliff collapse
Sequence of images showing different views of the Aswan cliff collapse on Comet 67P/Churyumov-Gerasimenko. The first image shows the fracture long before it gave away on 10 July 2015. Images taken on 15 July and 26 December show the bright, pristine material exposed in the cliff collapse, which is thought to have occurred on 10 July. Although not obvious from these images, the brightness had faded by about 50% by the 26 December image, showing that much of the exposed water-ice had already sublimated by that time. The images from 2016 show different views of the new cliff top. By August 2016, much of the cliff face had returned to the average brightness of the comet.
Arrows are used to mark the fracture and the exposed water-ice, and to delineate the new cliff top outline.
More information: Collapsing cliff reveals comet's interior
Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA