meteoriteimpact

Meteorite impact is the collision of a meteorite with a planetary surface, releasing kinetic energy that often forms a crater and distributes ejecta. Most small bodies burn up in the atmosphere, but larger ones survive to strike the surface. The impact energy, velocity, and angle determine the crater's size and morphology. The process includes an initial transient crater, followed by modification-stage collapse that produces a broader complex structure with an ejecta blanket and sometimes melt rocks.

Impact craters are identified by features such as fracture patterns, shocked minerals, and, in some cases, tektites or spherules. The surrounding ejecta may show a graded distribution of material; melt rocks and shocked quartz demonstrate rapid pressure and heating. On Earth, erosion and tectonics erase most craters, making well-preserved examples relatively scarce.

Investigations combine field mapping, geophysical imaging, drilling, and laboratory analysis. Isotopic and mineralogical evidence, such as iridium layers and shatter cones, help distinguish impact events from volcanic activity. Dating with radiometric methods places craters within geological timelines. Some impacts produced global effects, including extinction events and climate perturbations.

Notable examples include Barringer Crater in Arizona, Chicxulub in the Yucatán Peninsula (linked to the Cretaceous–Paleogene extinction), Vredefort in South Africa, and Sudbury in Ontario. Studying meteorite impacts informs planetary science, assesses hazard from near-Earth objects, and guides potential mitigation strategies.