Dinosaurs went extinct primarily due to a catastrophic event 66 million years ago, widely accepted to be the impact of a massive asteroid about 10 to 15 km wide, which created the Chicxulub crater in present-day Mexico. This impact caused a lingering "impact winter" by throwing dust, aerosols, and vaporized rock into the atmosphere, blocking sunlight and halting photosynthesis in plants and plankton, which disrupted the food chain on land and in the oceans. This event led to rapid and severe environmental changes that most dinosaurs could not survive. In addition to the asteroid impact, other contributing factors likely played a role, including extensive volcanic eruptions known as the Deccan Traps in India, which released large amounts of dust, sulfur aerosols, and carbon dioxide, causing further climate change, acid rain, and habitat disruption. There may also have been longer-term climate changes and sea level fluctuations that stressed ecosystems before the asteroid impact. In summary, the dinosaurs' extinction was caused by a combination of a massive asteroid impact and volcanic activity that together caused rapid environmental changes leading to a mass extinction event at the boundary between the Cretaceous and Paleogene periods. Only the lineage of dinosaurs that evolved into birds survived this extinction event.