How do central peaks develop in large impact craters?

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four impact craters — Meteorite crater Four impact craters of the same size (30 km [20 miles] in diameter) imaged by spacecraft on different solid bodies of the solar system and reproduced at the same scale. They are (clockwise from upper left) Golubkhina crater on Venus, Kepler crater on the Moon, an unnamed crater on Jupiter's moon Ganymede, and an unnamed crater on Mars. The images are oriented such that the craters appear illuminated from the left; the Venusian crater is imaged in radar wavelengths, the others in visible light.

In large impact craters, central peaks develop during the modification stage, which occurs when the initial parabolic cavity is too large to remain stable and begins to collapse.1

As the crater floor undergoes this collapse, material from beneath the impact site rebounds upward toward the center of the depression. This process is analogous to the backsplash and ripples observed when a pebble is dropped into water. While smaller complex craters may simply exhibit a flat floor due to this rebound, larger impacts generate a distinct central peak, and even larger events can result in a raised circular ring within the crater.1

This modification stage also involves downward faulting along the inner rim, creating terraces of material. Because these processes are difficult to simulate and occur at scales beyond those of terrestrial explosion craters, our understanding of them is primarily derived from field observations of Earth's impact structures and spacecraft imagery of other bodies in the solar system.1