2016-10-13. Comet may have struck Earth just 10 million years after dinosaur extinction.

posted Oct 15, 2016, 9:09 AM by Alan Gould
By Paul Voosen, Science. For GSS Life and Climate chapter 9. Excerpt: DENVER—Some 56 million years ago, carbon surged into Earth's atmosphere, raising temperatures by 5°C to 8°C and causing huge wildlife migrations—a scenario that might mirror the world's future, thanks to global warming. But what triggered this so-called Paleocene-Eocene thermal maximum (PETM) has remained a mystery. Now, in new work presented on 27 September at the annual meeting of the Geological Society of America and published this week in Science, a group of scientists bolsters its claim that a small comet impact kicked off the PETM, stirring up the carbon just 10 million years after a similar event decimated the dinosaurs. The group announced the discovery of glassy, dark beads, set in eight sediment cores tied to the PETM's start—spheres that are often associated with extraterrestrial strikes....  http://www.sciencemag.org/news/2016/10/comet-may-have-struck-earth-just-10-million-years-after-dinosaur-extinction