National Geographic News
A photo of a large asteroid hitting Earth 65 million years ago. The impact formed the Chicxulub crater.

An asteroid hitting Mexico's Yucatan some 66 million years ago is shown in this computer depiction.


Dan Vergano

National Geographic

Published May 12, 2014

The massive asteroid impact that ended the age of dinosaurs some 66 million years ago triggered a decades-long, deadly, global "impact winter," an analysis of ancient sediment confirmed on Monday. (Related: "What Killed Dinosaurs: New Ideas About the Wipeout.")

Sea temperatures dropped as much as 12.6 degrees Fahrenheit (7 degrees Celsius) after the Chicxulub crater blast blanketed the planet in ashy darkness, halting photosynthesis, concludes the team led Johan Vellekoop of Utrecht University in the Netherlands.

Massive hurricanes also struck during the impact winter, according to a report his team published in the Proceedings of the National Academy of Sciences.

Long suspected and now confirmed, the long-ago global winter has been seen as playing a major role in the mass extinction that followed the asteroid's impact in what is today Mexico's Yucatan. All dinosaurs—with the exception of birds—along with many marine reptiles and plant species, disappeared in the ancient calamity.

Volcanoes, wildfires, and tsunamis also added to the impact's deadly effects, with the catastrophe playing out over a century, according to the analysis.

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Raymond  Schep
Raymond Schep

If you want a brilliant treatise on an asteroid hit off the coast of N Carolina, and how it shifted the poles read the book by the German Engineer Otto Muck. The Secret of Atlantis.

Bro John Kenney
Bro John Kenney

With all the latest advances in technology it would probably be possible to spot an asteroid on a collision course with our planet. But, the question is, would we be able to prevent an impact? 

David Surace
David Surace

I see no other theory that makes any sense.

I do have a question: An asteroid of that size, hitting our planet with such a violent impact, could this have effected our orbit around the sun? Could we have been pushed out of orbit a bit effecting our temperature? Could our hours of daylight been effected. So many things are connected when it comes to our climate. We are but a blip in time.....we have almost our earth in a blink of an eye.

Ernest Dorko
Ernest Dorko

As a volunteer at our natural history museum this information is invaluable for me and for our visitors.  Thanks.

Ashley Davis
Ashley Davis

National Geographic,

It sometimes feels as if you are listining in on my classroom! At LEAST once or twice a week we will discuss a topic, and bam, the next day you have an article about it! Thanks National Geographic you add fun to my class discussions on a weekly basis :)

Nilas Ralph Sanders
Nilas Ralph Sanders

Seams to me humans are on a journey to something that is far beyond our minds.

Bob Eppler
Bob Eppler

If you fear knowledge, then you will be controlled. Don't fear it, use it. 


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