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Comment by rshnotsecure | Hacker News Reader

This is quite serious. Interstellar objects travel at very fast speed. Comets, because of their highly elliptical orbit, already impact earth at much higher speeds than asteroids. Can only imagine what a hit from something further than the Oort Cloud is.

It is very likely that the global flood monomyth is based on the impact of a comet around 13,000 years ago. This was somewhat discounted only 10 years ago, but now is more than the majority consensus in the field (“Younger Dryas Impact Hypothesis”).

Comet would have hit Greenland by the way, with many pieces falling apart and hitting North America. This would have destabilized the entire ice shield across that area.

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> This was somewhat discounted only 10 years ago, but now is more than the majority consensus in the field (“Younger Dryas Impact Hypothesis”).

Is it the "majority consensus"? The hypothesis' Wikipedia article (https://en.wikipedia.org/wiki/Younger_Dryas_impact_hypothesi...) has links to multiple recent articles arguing against it (in both the "Evidence" and "Criticism" sections), including ones like https://www.sciencemag.org/news/2018/11/massive-crater-under... suggesting that the Greenlandic impact event might have happened at the wrong time or not produced the widespread effects you and other proponents of the hypothesis suggest:

> Even if the asteroid struck at the right moment, it might not have unleashed all the disasters envisioned by proponents of the Younger Dryas impact. "It's too small and too far away to kill off the Pleistocene mammals in the continental United States," Melosh says. And how a strike could spark flames in such a cold, barren region is hard to see. "I can't imagine how something like this impact in this location could have caused massive fires in North America," Marlon says.

Lots of majority consensus ideas have papers criticizing them, and I don't see why Wikipedia would be a good place to look to determine that in any case.

The Wikipedia article doesn't agree with your assertion that this is "more than the majority consensus in the field", and presents lots of evidence against the hypothesis.

A more likely explanation for flood myths is that all ancient civilizations lived on the banks of mighty rivers that occasionally flooded.

Dunno, that seems a bit to regular. Humans weren't that stupid and rivers change all the time.

Seems much more likely it's something really unusual. Like say the Mediterranean basin and the resulting Zanclean flood. Back before humans were in North America it was a giant fertile basin with numerous rivers. Then one river that happened to come from the Atlantic ocean started to make some progress with erosion and kept getting bigger. The feedback loop turned into something that embarrasses Niagara fall by many orders of magnitude.

If you lived in the Mediterranean basin this would have made quite an impression. I believe this event was well depicted in https://xkcd.com/1190/ or https://blog.xkcd.com/2013/07/29/1190-time/

As big as that mega flood was, there have been others and certainly seems like very good source material for the numerous flood myths.

That flood is terrifying btw. I can barely watch the 3G geographic movie models without feeling terrified. That would have been 5 million years ago though I think. The #1 rule of humans and archaeology and anthropology is whatever your dates are, it probably happened sooner :)

But tough to imagine that flood could have been it (although amazing story) and agree with your final paragraph.

How does a comet cause a global flood? I couldn’t find any hypothesis regarding the link between comet impact and a global flood

Find some tsunami videos, the water just keep coming. A comet would produce a big wave.

It would not create a true global flood but it would create tsunamis and weather disruptions that could certainly by mythologized as such. Since humans are egocentric we would naturally assume it was our fault and that we offended the god(s).

There is no difference between a comet and a asteroid in this kind of situation, both would cause tsunamis.

On the other hand, having a huge fireball in the sky, earthquakes, ash falling from the sky, would probably leave an impression along with the tsunami (flood) that would be in the flood story. I seriously doubt the flood stories came from an asteroid or comet impact. Much simpler explanation is that it is a memory of either Black Sea forming or memory of the sea level rising at the end of the ice age.

> Can only imagine what a hit from something further than the Oort Cloud is.

Such a hit is extremely unlikely, extremely being a severe understatement. Imagine a solar system as a target, the size of a Mars orbit. If a fast-flying object from outer space manages to hit that target, its probability to hit earth is... 0,000000078%

If such objects will enter our Solar system every year, I'd say we're likely safe for the next few billion years. Sun turning into reg giant is a much more urgent issue.

What? The article makes no mention of the comet coming anywhere near the Earth. There is literally nothing to worry about here.

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