The comet which killed the Mammoths

AlpinLuke

Forum Staff
Oct 2011
27,051
Italy, Lago Maggiore
The YDIH, "Young Dyras Impact Hypothesis" is a fascinating theory which is gaining more and more geological clues and evidences supporting it.

If it will be proved, we could change a bit attitude regarding the catastrophism in general. The gradualist paradigm would receive a big hit [a comet impact ...].

Now, more that an entire comet, it was probably a group of fragments of a giant comet [today there would be still fragments of it orbiting not far from us in the "Taurids"] that hit our planet, in the Northern hemisphere around 12,900-12,800 years ago [provoking mass extinctions and the beginning of the Dyras period].

A wiki page as introduction:
https://en.wikipedia.org/wiki/Younger_Dryas_impact_hypothesis

The most intriguing aspect of this hypothesis is that a group of comet fragments would have exploded in the atmosphere and the biggest ones would have hit the glacial cap, substantially not leaving lasting craters [so that the most evident evidence of a cosmic impact, the crater, isn't]. We should remind that the glacial cap was kilometers thick and that a comet is not as solid and resistant as an asteroid.

The argument is matter of discussion in scientific environment and this article on National Geographic explains the hypothesis in detail:

Did a Comet Really Kill the Mammoths 12,900 Years Ago?
 

Robert165

Ad Honorem
Jan 2010
4,266
North Georgia
The YDIH, "Young Dyras Impact Hypothesis" is a fascinating theory which is gaining more and more geological clues and evidences supporting it.

If it will be proved, we could change a bit attitude regarding the catastrophism in general. The gradualist paradigm would receive a big hit [a comet impact ...].

Now, more that an entire comet, it was probably a group of fragments of a giant comet [today there would be still fragments of it orbiting not far from us in the "Taurids"] that hit our planet, in the Northern hemisphere around 12,900-12,800 years ago [provoking mass extinctions and the beginning of the Dyras period].

A wiki page as introduction:
https://en.wikipedia.org/wiki/Younger_Dryas_impact_hypothesis

The most intriguing aspect of this hypothesis is that a group of comet fragments would have exploded in the atmosphere and the biggest ones would have hit the glacial cap, substantially not leaving lasting craters [so that the most evident evidence of a cosmic impact, the crater, isn't]. We should remind that the glacial cap was kilometers thick and that a comet is not as solid and resistant as an asteroid.

The argument is matter of discussion in scientific environment and this article on National Geographic explains the hypothesis in detail:

Did a Comet Really Kill the Mammoths 12,900 Years Ago?
It sounds interesting.... I only read the first half of the article.... why is it such an unpopular idea? Lack of evidence or is it more than that???
 

AlpinLuke

Forum Staff
Oct 2011
27,051
Italy, Lago Maggiore
It sounds interesting.... I only read the first half of the article.... why is it such an unpopular idea? Lack of evidence or is it more than that???
Generally, there is a certain "resistance" about theories suggesting that similar catastrophes have happened in a so near past.

This is due to the matter of fact that what is called "catastrophism" has been the "kingdom" of some of the most odd loonies ever [prophets of the end of the world included!].

It's more a social than a scientific matter [scientists are persons and the scientific community is a kind of society, at the end].

Scientists have got no problems with near catastrophes: that comet impact would have simply delayed the end of the last period of wide glaciation [ice caps are still there, so to say "end of the last glacial period" is not so scientifically accurate] and when the ice withdrew, there was a global cataclysm caused by the arising level of the oceans [120mt ...], the change of the weight on the continental masses caused earthquakes [Scandinavia is still "emerging" since when the ice melted], tremendous local floods changed the geological aspect of some regions [think to the American "Scablands": that mess has been made by the water coming from the melting ice cap no more than 13,000 years ago!] ...

But there is a point: even in the events following the end of the last glacial expansion there was a certain gradual process. A part some localized extreme events, the global phenomenon was quite gradual.

That's the magical word: "gradual".

So, it's not that easy [a matter of mindset] to put a catastrophic event within a gradual process.

Then, discussion is still open and before a general agreement will be reached among scientists, we won't hear about that comet on general medias and we won't read about it on school books. It has happened the same with the asteroid which killed the dinosaurs ...
 

Robert165

Ad Honorem
Jan 2010
4,266
North Georgia
Generally, there is a certain "resistance" about theories suggesting that similar catastrophes have happened in a so near past.

This is due to the matter of fact that what is called "catastrophism" has been the "kingdom" of some of the most odd loonies ever [prophets of the end of the world included!].

It's more a social than a scientific matter [scientists are persons and the scientific community is a kind of society, at the end].

Scientists have got no problems with near catastrophes: that comet impact would have simply delayed the end of the last period of wide glaciation [ice caps are still there, so to say "end of the last glacial period" is not so scientifically accurate] and when the ice withdrew, there was a global cataclysm caused by the arising level of the oceans [120mt ...], the change of the weight on the continental masses caused earthquakes [Scandinavia is still "emerging" since when the ice melted], tremendous local floods changed the geological aspect of some regions [think to the American "Scablands": that mess has been made by the water coming from the melting ice cap no more than 13,000 years ago!] ...

But there is a point: even in the events following the end of the last glacial expansion there was a certain gradual process. A part some localized extreme events, the global phenomenon was quite gradual.

That's the magical word: "gradual".

So, it's not that easy [a matter of mindset] to put a catastrophic event within a gradual process.

Then, discussion is still open and before a general agreement will be reached among scientists, we won't hear about that comet on general medias and we won't read about it on school books. It has happened the same with the asteroid which killed the dinosaurs ...
There was a similar phenomena with the scablands (video)(wikipedia) in oregon/washington. Whereabout HUGE glacial lakes broke free and carved out canyons and depressions in the landscape that no one could understand. I seem to remember that the one scientist who believed in the theory made a presentation and there was another scientist in the audience who had a "key" piece of information but this other scientist was so scared of ridicule he never told the first guy the info needed to prove the theory. (He was scared of ridicule from other scientists).
 

AlpinLuke

Forum Staff
Oct 2011
27,051
Italy, Lago Maggiore
There was a similar phenomena with the scablands (video)(wikipedia) in oregon/washington. Whereabout HUGE glacial lakes broke free and carved out canyons and depressions in the landscape that no one could understand. I seem to remember that the one scientist who believed in the theory made a presentation and there was another scientist in the audience who had a "key" piece of information but this other scientist was so scared of ridicule he never told the first guy the info needed to prove the theory. (He was scared of ridicule from other scientists).
Correct. That was what I was making reference to saying that while the ice caps were melting local floods happened. The Scablands [as I've said] are a perfect example.

But that's not enough to prove the impact of fragments of a comet. A part a matter of scale [a cosmic impact on the ice cap should cause well wider floods, depending on where it hits], but some regions present the effect of impressive local floods.

Anyway, it's the presence of nanodiamonds and other particular formations in the layer of the Dyras to suggest an astronomical event.
 
Sep 2014
941
Texas
I've always supported the impact theory, and the all destructive fire from heaven could be a memory in myth the same way the floods are remembered.
 

AlpinLuke

Forum Staff
Oct 2011
27,051
Italy, Lago Maggiore
I've always supported the impact theory, and the all destructive fire from heaven could be a memory in myth the same way the floods are remembered.
The impact theory explains a couple of main events: the Young Dyras winter [which would be the consequence of the impact] and the enormous continental floods: if a good part of the fragments of the comet hit the glacial cap [a fragment fell in modern Syria].

The problem which is still to be explained is why after that "winter" the glacial age ended.

A possible explanation would be that the "train" of orbiting fragments of the original giant comet met again our planet, so that a new series of minor impacts affected again the climatic history of our planet.

But how?

Well, a fragment of a comet with a great content of hydrocarbons, falling in the oceans could send to the high atmosphere enormous masses of water vapor and hydrocarbons. The water vapor is among the most efficient greenhouse gasses ever [in some circumstances even better than methane].
 
Sep 2014
941
Texas
The impact theory explains a couple of main events: the Young Dyras winter [which would be the consequence of the impact] and the enormous continental floods: if a good part of the fragments of the comet hit the glacial cap [a fragment fell in modern Syria].

The problem which is still to be explained is why after that "winter" the glacial age ended.

A possible explanation would be that the "train" of orbiting fragments of the original giant comet met again our planet, so that a new series of minor impacts affected again the climatic history of our planet.

But how?

Well, a fragment of a comet with a great content of hydrocarbons, falling in the oceans could send to the high atmosphere enormous masses of water vapor and hydrocarbons. The water vapor is among the most efficient greenhouse gasses ever [in some circumstances even better than methane].
I'm just throwing this out there....could the comet have shifted the earth's tilt? The earth is a top and when it leans too far in one direction
it is cold or hot....read once that if it were straight up and down there would be no seasons. I am by no means an authority on this, but considered myself an educated amateur.
 

redcoat

Ad Honorem
Nov 2010
7,810
Stockport Cheshire UK
The human comet.
That's my belief as well. The spread of modern man out of Africa occurred just before the extinction of a number of large animal species which were known to have been hunted by them.
Add in a period of climate change, it's a fatal mixture.