Cosmic impact event

According to an article on Physics.org:

About 12,800 years ago when the Earth was warming and emerging from the last ice age, a dramatic and anomalous event occurred that abruptly reversed climatic conditions back to near-glacial state. According to James Kennett, UC Santa Barbara emeritus professor in earth sciences, this climate switch fundamentally –– and remarkably –– occurred in only one year, heralding the onset of the Younger Dryas cool episode. The cause of this cooling has been much debated, especially because it closely coincided with the abrupt extinction of the majority of the large animals then inhabiting the Americas, as well as the disappearance of the prehistoric Clovis culture, known for its big game hunting.

By examining microspherules in the geological strata of North and South America, Europe, and the Middle East, a research team has concluded that a catastrophic cosmic impact event caused continent-wide wildfires,and threw enough dust into the atmosphere to block significant amounts of sunlight, leading to the destruction of the American megafauna.

The impact that scooped out the Caribbean and killed the dinosaurs was 65 million years ago, but this impact was comparatively recent. One wonders what the odds are of it happening again.