Dinosaurs went extinct primarily due to a massive asteroid impact about 66 million years ago, marking the end of the Cretaceous period and the Mesozoic era. This asteroid, estimated to be 10 to 15 kilometers wide, struck the Earth near what is now the Yucatán Peninsula in Mexico, creating the Chicxulub crater
. The impact caused immediate devastation and triggered a global environmental catastrophe, including a prolonged "impact winter" where dust and aerosols blocked sunlight, halting photosynthesis in plants and plankton, which disrupted food chains both on land and in the oceans
. In addition to the asteroid impact, other factors likely contributed to the extinction event. Massive volcanic eruptions known as the Deccan Traps in present-day India released large amounts of dust, sulfuric aerosols, and greenhouse gases like carbon dioxide, which may have caused climate changes such as global warming and acid rain
. These volcanic activities, combined with sea level changes and climate shifts, stressed ecosystems over time, weakening dinosaur populations before the asteroid impact delivered the final blow
. Some scientists propose a combination of causes, including volcanism, asteroid impact, and other environmental stresses, leading to a two-pulse extinction pattern observed in some fossil records
. The overall effect was the extinction of all non-avian dinosaurs and many other species, with only some small, resilient animals surviving
. In summary, the extinction of dinosaurs was mainly caused by the catastrophic effects of a giant asteroid impact, compounded by volcanic activity and environmental changes that together led to a mass extinction event
