Uploaded March 2021 | Updated September 2026, 1 day ago
This video shows how a central peak forms in a model impact crater. The craters are produced by shooting a sand and microbead layer pack with a lead pellet from a high-power air rifle. The layer pack consists of a thin, "strong" (high friction due to angular particles) sand layer atop a thicker layer of glass microbeads, which are spherical and treated to have low friction against one another. This layer combination appears to be necessary to form a central peak with the impactor used; sand or microbeads alone won't do it.
Overall, the formation of the central peak is much like the splash that occurs when a pebble is dropped into calm water.
I don't know how these models scale to real planetary bodies. The microbeads are necessary for the developing crater to contain "strength-less" material in its transient phase. The strengthless beads behave in a fluid-like fashion as they collapse inward to restore an equilibrium with gravity and their surroundings.
This video shows how a central peak forms in a model impact crater. The craters are produced by shooting a sand and microbead layer pack with a lead pellet from a high-power air rifle. The layer pack consists of a thin, "strong" (high friction due to angular particles) sand layer atop a thicker layer of glass microbeads, which are spherical and treated to have low friction against one another. This layer combination appears to be necessary to form a central peak with the impactor used; sand or microbeads alone won't do it.
Overall, the formation of the central peak is much like the splash that occurs when a pebble is dropped into calm water.
I don't know how these models scale to real planetary bodies. The microbeads are necessary for the developing crater to contain "strength-less" material in its transient phase. The strengthless beads behave in a fluid-like fashion as they collapse inward to restore an equilibrium with gravity and their surroundings.
