K–T extinction: Quick Facts

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Last updated

Sep. 14, 2026

Facts

Also Known As	Cretaceous–Paleogene extinction • Cretaceous–Tertiary extinction • K–Pg extinction

Photos and Videos

Line graph showing the number of marine animal families from the Precambrian era to the present, with illustrations of key groups such as trilobites, ammonoids, marine reptiles, and diatoms. The graph highlights major extinction events and a rise to 1,900 living families today.

Multiple spiral-shaped ammonite fossils embedded in a rough rock matrix, showing detailed ridges and whorls against a black background.

The Chicxulub asteroid

Chicxulub crater

computer-generated image of the Chicxulub crater

Illustration showing a massive asteroid above a city map with a dinosaur silhouette for scale, highlighting the asteroid's size compared to major urban areas.

How did dinosaurs go extinct?

Earth's history: What happens after a meteorite impact?

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Topics

How Big Was the Asteroid That Contributed to Dinosaur Extinction?dinosaur Tertiary Period Cretaceous Period rudist K–T boundary ammonoid belemnoid Paleogene Period Gryphaea Permian extinction Devonian extinctions end-Triassic extinction Ordovician-Silurian extinction Major Mass Extinctions