The Younger Dryas impact hypothesis or Clovis comet hypothesis is the hypothesized large air burst or earth impact of an object or objects from outer space that initiated the Younger Dryas cold period about 12,900 BP calibrated (10,900 BP uncalibrated) years ago. The hypothesis has been largely questioned by research that stated that most of the conclusions cannot be repeated by other scientists, misinterpretation of data, and the lack of confirmatory evidence.
The hypothesized impact event scenario stated that the air burst(s) or impact(s) of a swarm of carbonaceous chondrites or comet fragments set areas of the North American continent on fire, causing the extinction of most of the megafauna in North America and the demise of the North American Clovis culture after the last glacial period. The Younger Dryas ice age lasted for about 1,200 years before the climate warmed again. This swarm is hypothesized to have exploded above or possibly on the Laurentide Ice Sheet in the region of the Great Lakes, though no impact crater has been yet identified. An airburst would have been similar to but orders of magnitude larger than the Tunguska event of 1908. The hypothesis proposed that animal and human life in North America not directly killed by the blast or the resulting coast-to-coast wildfires would have likely starved on the burned surface of the continent.
Read more about Younger Dryas Impact Hypothesis: Evidence, Consequences of Hypothetical Impact, History of The Hypothesis, Criticism
Famous quotes containing the words younger, impact and/or hypothesis:
“When you are younger you get blamed for crimes you never committed and when you’re older you begin to get credit for virtues you never possessed. It evens itself out.”
—I.F. (Isidor Feinstein)
“Television does not dominate or insist, as movies do. It is not sensational, but taken for granted. Insistence would destroy it, for its message is so dire that it relies on being the background drone that counters silence. For most of us, it is something turned on and off as we would the light. It is a service, not a luxury or a thing of choice.”
—David Thomson, U.S. film historian. America in the Dark: The Impact of Hollywood Films on American Culture, ch. 8, William Morrow (1977)
“The wheels and springs of man are all set to the hypothesis of the permanence of nature. We are not built like a ship to be tossed, but like a house to stand.”
—Ralph Waldo Emerson (1803–1882)