Which event is believed to have caused the extinction of the dinosaurs around 65 million years ago?

Which event is believed to have caused the extinction of the dinosaurs around 65 million years ago?

• A. Volcanic eruptions.
• B. Global cooling.
• C. Supernova.
• D. Asteroid impact.

Answer: (D)

A massive asteroid impact at the end of the Cretaceous is what the evidence supports. About 65–66 million years ago, an asteroid struck Earth, creating the Chicxulub crater and blasting enormous dust and sulfate aerosols into the atmosphere. This material would have blocked sunlight, disrupted photosynthesis, and caused rapid climate cooling, contributing to a global collapse of ecosystems. The worldwide layer rich in iridium, along with shocked quartz and geological signs of massive tsunamis, lines up with a sudden extraterrestrial impact rather than gradual environmental change. While extensive volcanic activity around the same time could have stressed ecosystems further, the strongest, most consistent indicators point to the asteroid being the primary trigger. The other scenarios—long-term cooling alone, a supernova, or eruptions causing the extinction without the asteroid’s global signatures—do not fit the observed evidence as well as an abrupt, asteroid-driven event.

A massive asteroid impact at the end of the Cretaceous is what the evidence supports. About 65–66 million years ago, an asteroid struck Earth, creating the Chicxulub crater and blasting enormous dust and sulfate aerosols into the atmosphere. This material would have blocked sunlight, disrupted photosynthesis, and caused rapid climate cooling, contributing to a global collapse of ecosystems. The worldwide layer rich in iridium, along with shocked quartz and geological signs of massive tsunamis, lines up with a sudden extraterrestrial impact rather than gradual environmental change. While extensive volcanic activity around the same time could have stressed ecosystems further, the strongest, most consistent indicators point to the asteroid being the primary trigger. The other scenarios—long-term cooling alone, a supernova, or eruptions causing the extinction without the asteroid’s global signatures—do not fit the observed evidence as well as an abrupt, asteroid-driven event.