© Don Davis/NASA
Debris kicked up by a large asteroid rained back down on the Earth, heating up as it fell. But new research suggests that the first debris to re-enter the atmosphere shielded the surface from the heat of later infalling debris, preventing the world's forests from igniting
Debris kicked up by a large asteroid rained back down on the Earth, heating up as it fell. But new research suggests that the first debris to re-enter the atmosphere shielded the surface from the heat of later infalling debris, preventing the world's forests from igniting
The impact of a 10-kilometre asteroid is blamed for the extinction of the dinosaurs and most other species on the planet. Early computer models showed that more than half of the debris blasted into space by the impact would fall into the atmosphere within eight hours.
The models predicted the rain of shock-heated debris would radiate heat as intensely as an oven set to "broil" (260 °C) for at least 20 minutes, and perhaps a couple of hours. Intense heating for that long would heat wood to its ignition temperature, causing global wildfires.
