How do asteroid impacts create craters on planets and moons?

When an asteroid strikes a planetary surface at hypervelocity—traveling at tens of kilometers per second—it releases an immense amount of kinetic energy in a localized area, a process physically comparable to an atomic bomb explosion.1

Upon impact, shock waves are imparted to both the surface and the asteroid, which is typically vaporized. These waves dissipate energy, creating zones of melted and crushed material. A subsequent release wave generates pressure gradients that project material upward and outward, forming a parabolic bowl-shaped depression.1

The resulting crater type depends on its size:
* Simple craters: Smaller depressions where the formation process ends after excavation.1
* Complex craters: Larger structures that undergo a modification stage. Because the initial cavity is too large to support itself, it collapses, often resulting in a flat floor, a central peak, or internal rings caused by material rebounding toward the impact point.1

Excavated material, known as the ejecta blanket, surrounds the crater, with the highest elevation forming an elevated rim.1