Catastrophe that killed dinosaurs created global hothouse for 100,000 years, study says

On a very bad day 66 million years ago, a mountain-sized object from space slammed into the Earth, initiating a cascade of calamities that eradicated three-fourths of the species on the planet, including the non-avian dinosaurs. The buried remnants of the 125-mile-wide crater have been identified on the Yucatin Peninsula and in the Gulf of Mexico. Scientists have long theorized that an initial pulse of heat was followed by a devastating global winter. After that, as carbon dioxide in the atmosphere surged, the planet became a hothouse.