Clementine Collection

The Aristarchus impact occurred relatively recently in geologic time, after the Copernicus impact but before the Tycho impact. The 42-km-diameter crater and its ejecta are especially interesting because of the location on the uplifted southeastern corner of the Aristarchus plateau. As a result, the crater ejecta reveal two different stratigraphic sequences: that of the plateau to the northwest, and that of a portion of Oceanus Procellarum to the southeast. This asymmetry is apparent in the colors of the ejecta as seen in this image, which is reddish to the southeast, dominated by excavated mare lava, and bluish to the northwest, caused by the excavation of highlands materials in the plateau. The extent of the continuous ejecta blanket also appears asymmetric. The blanket extends about twice as far to the north and east as it does in other directions, approximately following the plateau margins. These ejecta lobes could be caused by an oblique impact from the southeast, or it may reflect the presence of the plateau during ejecta emplacement.

A high resolution image is also available. Warning: this image is very, very, large (62 Mbytes)!!!!

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