Simulation of tsunami from dinosaur-killing asteroid that brought 2.5 mile waves | Hacker News Reader

Simulation of tsunami from dinosaur-killing asteroid that brought 2.5 mile waves

sos.noaa.gov

205 pointsindigodaddy153 comments

> 30,000 times more initial energy than any recorded events

As a statistician: this is why heavy-tailed modeling matters. Schools teach the finite-variance version of the Central Limit Theorem and students believe they live in a normal world. The real Central Limit Theorem [1] predicts large rare events following Lévy α-stable distributions.

[1] https://en.wikipedia.org/wiki/Stable_distribution#A_generali...

This is so true. Heavy-tailed distributions and extreme value theory [1,2] should be taught more widely.

The normal distribution is just a very particular case of the generalized CLT.

For example, some drug effects are heavy-tailed, but safety trials are often ignoring this.

[1] https://adamwierman.com/wp-content/uploads/2020/09/2013-SIGM...

[2] https://adamwierman.com/wp-content/uploads/2021/05/book-05-1...

> some drug effects are heavy-tailed

where can i read about this? curious

Got any sources which discuss the heavy-tailed effects of drugs and how they're ignored by safety trials? I'd love to read more!

I don't have references with me right now, but there are quite a few reputable studies that have found effects to be log-normal.

Log-normal is a quite nasty heavy-tailed distribution as it's easy to take it for normal if you have small sample sizes.

This has tricked the safety calculations of a few trials. I don't think it's too worrying or generalized, just some area to improve.

It would save quite a few ocean going ships if this was more appreciated. Those once-in-a-thousand-year-rogue-waves are much more frequent than once in a thousand years.

https://www.theguardian.com/science/2006/jul/26/uknews

But we're still designing ships as though they only happen once every thousand years because the cargo and the ship are insured and the crews are considered expendable.

> Research at Imperial College, London, shows that far from being rare events, rogue waves can emerge frequently, and may be responsible for some of the 200 supertankers and container ships longer than 200m that have sunk in poor weather conditions in the past two decades.

The loss of ten ships a year seems incredible to me. Surely "weather", if it were to blame, could be avoided.

This amount of loss is steep. Is it being investigated? We should have ocean swell data beamed to satellite from every ship that capsizes.

https://www.statista.com/statistics/1326758/number-of-oil-ta...: There were 8,883 oil tankers worldwide in 2021.

If those are all ocean-going, ten a year is about 1.1%. Depending on how expensive it would be to prevent this, that may not be bad for ship owners, but it is very bad for those seeking a career in working on those ships.

1.1% of what?

Of ocean-going oil tankers.

It's ~0.11% of those

Relative to what other transportation profession, though? Pilots, truck drivers, train operators? All of them have deadly accidents.

plus 5,589 containerships

https://www.statista.com/statistics/198227/forecast-for-glob...

although the parent comment mentioned "longer than 200m" but its difficult to find containership stats by length rather than by TEU.

ignoring that though it would be 0.07% lost per year or 1 out of every 1447.

probably not too surprising, since if you pick 1447 oil tankers/containerships and audit them consider what the worst looking one is going to look like after decades of salt damage and abuse and poor maintenance.

'Surely "weather", if it were to blame, could be avoided.'

AFAIK rogue waves are called 'rogue' due to their unpredictability.

Nomenclature aside, they're somewhat predictable in the sense that if the most dangerous rogue waves will typically happen in or near low preasure systems, and especially around strong currents, where you have wind-over-tide type nastiness.

So in the sense of trying not to die, avoid the Gulf and Agulhas currents, especially when a low blows through.

This coming from an amateur sailor. I believe freight shipping etc just plows through most weather systems in order to avoid delays.

There are also source of loss, nothing can be done against. One can not even predict them.

Ocean floor methanhydrate and a volcanic shift, results in tremendous bubble columns, which just open up a shaft that can carry nothing. Water begins to boil, ship falls in, breaks apart... End of story.

Surely the gas-producing seafloor distribution can also be studied and modeled.

How many incidents of this have there been? I've heard of the theory, but no actual losses attributed to it.

Because a few ships a year are expendable for the global economy.

Not worth it to try to make every ship less sinkable - e.g. it may decrease the number of annual losses by 50% at the cost of making an average ship 10% more expensive - obviously a bad trade. Some ships will still sink, because of stuff like human errors.

You know that ships have crew in it?

Yeah, and?

How much do you think the humankind is willing to pay to save a human live - a million dollars, a billion, a trillion?

A lot more than it does at the moment, certainly. That's no bad thing either, even if insurance premiums would go up (and construction quality would then improve to compensate and bring them somewhat back down, and finally fewer incidents would result in loss of life.)

https://en.m.wikipedia.org/wiki/Value_of_life

The crew probably has a good idea of the risks

I'm not sure they do - are they oceanographers? These are very rare events; very few crewmembers have experienced such waves.

Also, even if they do, it doesn't stop them from being exploited.

If you have an idea of the risks involved, then certainly people who are embedded in sea-going culture do as well.

Occupational safety doesn't happen just because you think it should. Recognizing when financial incentives are insufficient is important to designing a realistic solution.

This trade-off is everywhere. As a society, we choose to have some people die due to speeding instead of making speed limits 15mph, which would absolutely make roads safer. Human life just doesn't trump all else - we factor in other things.

And a company would go broke trying to secure itself against every conceivably IT security threat, so IT security aims to keep breaches out of the headlines rather than eliminate them completely.

Your own skeletal system is a trade-off of different factors.

Is there a statistics about ships sinking because of rogue waves?

Recent news story:

>One passenger was killed and four more injured after a "rogue wave" hit a cruise ship bound for Antarctica, travel company Viking has said.

https://www.bbc.com/news/world-latin-america-63846157 (Dec 2022)

Heavy-tailed modeling doesn't reallly matter. There are very few enterprices where preparing for extremely rare events is worth the effort - nuclear power plants, weapons of mass destruction, bio labs working with dangerous organisms, big chemical plants, maybe AI research and big particle accelerators.

the most important of all - your 401k

What does a 401k have to do with extremely rare events?

Preparing for stuff like a nuclear war would mean buying land in South America, Africa or Australia, building an underground bunker, stacking on water, food, medicine and weapons, etc.

so you buy an index fund or ETF. capture some of the positives if/when they happen, and help mitigate the negatives

some would argue performance of the 60/40 portfolio last year was an event from a tail of a very non-normal distribution

If you tuned out of current events, financial and otherwise, five years ago - in early 2018 - and your 401k was entirely on autopilot in an S&P 500 fund, it looks like your average annual return would've been about 11.5%, annual US inflation was 3.7%, and return after inflation 7.5%. Per year. You can't reasonably expect better.

And practically speaking, the tax avoidance means that's considerably better than 11% in a non-retirement account, but it was too much effort to do the math.

Despite all the pestilence, war, earthquakes, and stuff like that, doing nothing was the smart move again, with $1 or $1 million.

I don't think it makes sense to prepare for a global collapse of civilization because in the event whatever you will reap won't make hardly any difference in how much things suck. You can't eat money, much less use it as a shelter from a global rain of molten rock.

So on principle, regardless of the probability of Armageddon, I don't think one should give up much to try to hedge the end of the world.

I'm no expert on stats, this discussion is a bit over my head, but it reminds me that not all distributions have a mean. A Cauchy distribution has no mean; as you average successive samples, it never settles down to a consistent average. I was surprised when I first encountered Cauchy distributions and up until then had considered that all distributions would have a mean. I suppose it is one of those "heavy-tailed" distributions you're talking about?

It’s an example but long tailed distributions can have a mean, and short tailed distributions can have no mean. It’s not indicative.

> short tailed distributions can have no mean

That’s a surprise to me. Now I’m curious: With what definition of “short tailed” can that be true?

There’s no need to get mathy tbh. Distributions are not real, and the ones we create only describe parts of what actually happens. This is obvious and always has been.

How much water does your faucet leak per day? That might be a good case for a normal distribution. But today I smack it with a hammer and it can’t stop flowing. We now have a ton of water far more than should ever appear on that original normal distribution. Is that because the model is wrong? No. It’s because the model is not designed for these circumstances.

We can’t build a model that estimates flow distribution including the possibility that I smack it with a hammer. That doesn’t mean we don’t believe it won’t ever happen or even that we think it is unlikely to happen. It’s just a weird edge case.

A lot of people (taleb) imply statisticians are idiots because they insist the distributions are comprehensive. But statisticians don’t insist this. Black swan, fat tails, and all that are just terms for things outside modeled conditions. And yeah. They happen.

If you work in finance and your competitors attended those universities you have an edge.

The central limit theorem applies to sample means, not individual events. I’m not sure it has any relevance to predicting the probability of a single large outlier tsunami

Just to put the numbers in slightly easier to imagine numbers: imagine ocean waves about 13000 feet or 4 kilometers high.

No, I can't really imagine it either.

In San Francisco, the tallest building is the Salesforce Tower at 1070ft. The biggest wave would be about 13 times taller than that.

I totally have trouble visualizing it, other than just looking up and up and up.

Mt. Fuji stands at 3.8km (12,467ft). They say the wave reached 4.5km, so maybe Mt. Fuji with the Burj Khalifa (~800m) on top? Still very difficult to picture as a wall of water.

Those aren’t mountains.

The best hope would be that the mountains and ground whittle it down and that it drains quickly. May explain why rodents survived, in that dry to moderately dry ground doesn't soak up water quickly, so if it drained away before the burrows were soaked/drowned, there is a chance at survival.

Likely such a wave would scour the coastline many, many miles inland and the land would essentially have to be re-settled all over again by all of the life forms that thrived there before. There is very little chance that a burrow would not be flooded, but many rodents are good swimmers and there will be lots of stuff floating about.

There was a lot more to worry about than the wave. Anything within about 1500 km of the impact site was instantly vaporised. Then afterwards the whole atmosphere was oven-hot for several minutes. Then there was very little sunlight for decades. https://www.youtube.com/watch?v=dFCbJmgeHmA

Is it the consensus that the entire planet's atmosphere was oven hot from re-entering ejecta, or is that just one particular model? I've heard various claims about the dinosaur extinction event, from the nuclear winter type scenario to all the non-avian ones dying with in an hour to a day after the impact. I've also heard different nuclear holocaust scenarios from the nuclear winter lasting as long as 10-15 years, to there being no nuclear winter, all depending on whether the burning material reaches the stratosphere in large amounts.

Safe to say we don't have real world examples to test at planetary scale, so I'm a little skeptical as to how accurate any of these models are. We just know the result was a planetary-scale extinction event for at least 60% of life, although there is also the possibility of multiple impacts, and previous volcanic activity aiding the extinction.

The article reads to me like the 4.5 km wave was an initial "splash" which dissipated but the actual tsunami was "only" 1.5 km high. Imagine throwing a good sized rock into a pond: Big initial splash, then smaller waves radiate out. Of course, to observe the proper effect, you would need to throw your rock at 20 km/s into shallow water.

> a curtain of ejected material pushed a wall of water outward from the impact site, briefly forming a 4.5 kilometers high (2.8 miles) wave that subsided as the ejecta fell back to Earth. Ten minutes after the projectile hit the Yucatan, and 220 kilometers (137 miles) from the point of impact, a 1.5 kilometers high (0.93 miles) tsunami wave—ring-shaped and outward-propagating—began sweeping across the ocean in all directions

Is it closer to Interstellar's wave planet?

more like Deep Impact's wave I'd imagine. Though the wavefront there probably looks too sharp?

Deep Impact's wave was barely taller than the WTC towers.

4.5km would dwarf that.

Hm, I have much more difficulty imagining how far inside the shoreline that would go - so if I take a port city, is it wiped off completely? Does it matter if it goes uphill for 10km? 100km?

I was wondering the same. the simulation doesn't appear to account for the landmasses, treating them as impenetrable barriers. where is the flooding simulation? are we to assume the shores were 5km high vertical rock?

One of the science show (Nova ? could not find it quickly) did an extinction event analysis on a point far upstream a river and tied it to the Chicxulub event. The local flora and fauna were killed by water flow high up river and hot ash rain.

When I went to the Grand Canyon I was surprised at how little my brain could comprehend the depth. There are so many false bottoms, when you're up on the rim, you look down and you see something you think is the bottom, but then you realize there's still a canyon below that, then you look down into that canyon and find the bottom, and then you realize there's still a canyon below that. It's like your brain absolutely cannot process being 2 kilometers above the bottom. That's what I thought of when I read your post.

(I had a similar feeling when I was in the High Atlas mountain range in Morocco and tried to look up to the top)

I can visualize: the highest peak around me is 3200 km

m not km I presume

That’s the moon. ;-)

And this would be in the context of the atmosphere vaporising followed by a massive shockwave and a 10km mountain of the earths crust rising up towards the sky at the point of impact. https://www.youtube.com/watch?v=dFCbJmgeHmA

When I went skydiving, they took me up to 12.5k feet. Good weather was necessary, and they offered to only go to 9k feet if I was a little "scared". Not sure why jumping out of a plane at 9k feet is any more reassuring... A wave that tall is insane.

Consider that the peak of Olympus Mons[1] on Mars is 26 km (16 mi) above the plain.

It's unlikely that it's the tallest mountain in the universe, though, and a true pity that if the current understanding of physics is correct, and we can not travel faster than the speed of light, no human will ever experience those massive, distant mountains outside our solar system except in images or virtual reality.

[1] - https://en.m.wikipedia.org/wiki/Olympus_Mons

Don’t imagine it as a wave like one people surf on. Imagine it as a tide.

Either way I'm imagining "The ocean is suddenly 4km higher than it normally is".

There are a large number of events taht have happened many times in Earth's history and, given the cosmic timelines, will happen again, repeatedly. Some may be preventable with technology (eg asteroid impacts), others less so.

A partial list is: tsunamis, earthquakes, volcanoes, supervolcanoes, flood basalts, asteroid impacts, magnetic field reversals, climate change (eg ice once covered the equator, North America used to be covered in an ice sheet a mile thick not that long ago), particles in the atmosphere blocking the Sun, supernovas, gamma ray bursts, solar flares and coronal mass ejections.

It's kind of amazing we're here at all.

More amazing to realize without any of those things we wouldn't be here!

Wow thinking about it from that perspective is also kind mind-blowing. Interesting point!

The Carrington event where a solar flare turned telegraph wires into those electromagnetd you build in elementary school. The current from the storm electrified all the telegraph cables. This would be bad for anything we've built that has a long cable run...

https://podcasts.google.com/feed/aHR0cHM6Ly9mZWVkcy5tZWdhcGh...

Or how 536 was the worst year on record (and no one really knows why)

https://podcasts.google.com/feed/aHR0cHM6Ly9mZWVkcy5tZWdhcGh...

> Or how 536 was the worst year on record

Although I didn't listen to the 11 minute podcast, I was curious to know basically what it was about. This is what Wikipedia says about year 536:

"In 2018, medieval scholar Michael McCormick nominated 536 as 'the worst year to be alive' because of the extreme weather events probably caused by a volcanic eruption early in the year, causing average temperatures in Europe and China to decline and resulting in crop failures and famine for well over a year. Other researchers have noted additional adverse events during the year, including a mysterious fog, possibly due to the volcanic eruption."[1]

[1] https://en.wikipedia.org/wiki/536

A single source of quote, and I really doubt we can find anything related in recorded history. The history books of China definitely didn't mention anything significant about year 536.

They should, a global darkening of the skies due to an unknown volcano or volcanoes (or something else that spewed massive amounts of dust into the atmosphere).

There’s a solid amount evidence showing that there was some kind of abnormal volcanic winter in 536.

https://en.m.wikipedia.org/wiki/Volcanic_winter_of_536

Whether it was “the worst year in history” is probably tough to quantify and prove, though.

Here[1] is one of the most impressive asteroid impact simulations I have seen, from the Discover Channel's Miracle Planet.

[1] - https://m.youtube.com/watch?v=PENT_hnyO-o

In the video, they said an impact like that happened an estimated 6 times and each time, life sprung back. The whole surface was sterilized.

This makes me think that if life comes back after that 6 times, then it must be pretty easy for life to start.

Starting life is very different from recovering it. Luckily none of those asteroids killed all life.

In this particular Youtube video, they mentioned that the object that hit Earth was 500km or roughly 38 times larger than the one that killed the dinosaurs. I could believe that the Earth was sterilized from an impact that large.

When did it hit though, do we even know if life had started yet?

> This makes me think that if life comes back after that 6 times, then it must be pretty easy for life to start.

Or that they are wrong and the whole surface was not in fact sterilised. Or life survived somewhere other than on the surface (deep underground, underwater, or high in the sky).

Seems likely that some single cell life could survive in some deep cave system

There may not have been life before that. In the video they just say that if there was life it would have to begin anew.

That seems like a bad model if it does not include the effects of the waves penetrating inland and instead acts as if the coasts are inviolable.

This particular event happened 66M years ago, it would be wild guess to include effects on land that may have or haven't existed then.

I don't see why it would be any more of a wild guess than the guess at what rock layers were hit by the asteroid and what effect they had at displacing water.

I also wonder if the model also accounts for vapourisation. Over the entire ocean, the effect may be negligible, but local to the impact may have made a non-trivial difference.

Most of these asteroid impact models are also missing the secondary impact events from ejecta. For very small asteroids it's not much of a concern but anything large enough to be dangerous would kick out enough material to create a storm of falling superheated boulders. Big enough asteroids can blast stuff into orbit which then falls all over the Earth.

Superheated as opposed to plainly-heated?

As cool as that is, I'm more interested in seeing how far inland the waves would go.

Same. Shocking to see how the waves wrapped around the peninsula though. But also, was the impact site actually ocean when it was hit, or was it flooded after impact?

It was ocean but it was sort of like hitting a shallow puddle for a 10 km diameter rock.

The article didn't say but I was also curious and looked it up on Wikipedia:

> The water depth at the impact site varied from 100 meters (330 ft) on the western edge of the crater to over 1,200 meters (3,900 ft) on the northeastern edge.

https://en.wikipedia.org/wiki/Chicxulub_crater#Impact_specif...

True, but it would depend on local topography/geography. I'd guess from a couple of miles up to a hundred miles inland in some places.

The press release says that there are plans to look at inundation.

https://news.umich.edu/dinosaur-killing-asteroid-triggered-g...

They do say that airborne water and sediment traveled several hundred kilometers.

It also has some more details about wave height: "their models indicate that open-ocean wave heights in the Gulf of Mexico would have exceeded 100 meters (328 feet), with wave heights of more than 10 meters (32.8 feet) as the tsunami approached North Atlantic coastal regions and parts of South America’s Pacific coast."

Kurzgesagt did a pretty good job of this https://youtu.be/dFCbJmgeHmA

I remember those waves on interstellar being a scarier adversary than Pennywise from IT. It must have been quite a sight. I wonder if any of the creatures from the event felt fear before the water washed over them.

I have long said that if I was given the chance to go back in time just once, and come back, I would return 66 million years ago to witness the meteor impact from the safety of a space shuttle.

And now I have an idea for Elon Musk: interplanetary disaster tourism. Purposefully crash asteroids on remote areas of Mars and charge for front row seats. This would have the added benefit of bringing valuable metal ores to be harvested close to the demand source.

These would make amazing VR experiences

Hummmm VR tourism on Mars, that reminds me of something... But it might not be a great idea if the VR is too realistic /s

My most memorable VR experiences were a jellyfish/turtle scene and a closeup of a whale, among several games and apps I tried with my headset some years ago.

Games were fun enough, some good, some not. The visual, non-interactive experience gave me a true sense of awe, as if I were transposed into another reality briefly. Not a big fan of the whole "meta" idea, but executed and refined properly, we'll be in the matrix soon enough. Glad I won't be participating :)

"The Blue" was indeed amazing.

Back then, I showed it to visitors at work (besides real projects) and it never failed to impress.

I think with simulation work like the OP, and Hollywood CGI, we could produce a better virtual view of the event than you could get from any safe distance.

There is indeed a VR simulation available for the asteroid impact.

To terraform mars we'd need 3500 nukes per day for 7 weeks. That would be quite a show!

but... why..?!

Always nice to have a second habitable planet.

Nuking it wouldn't make it any more habitable.

At best you'd make the surface slightly warmer and maybe melt some leftover CO2 on the poles.

To actually terraform it to anything resembling even an Earth desert, you'd need incomprehensible amounts of energy.

I don't expect it to work either. But there is probably enough water. Maybe not other stuff.

LEO may not even be safe, would it? Afaik a large part of the damage was the heating of the atmosphere from enormous amounts of secondary impacts due to the debris - many of these small rocks probably flung up into LEO, though it would be interesting to know how risky a stay in LEO would be during such an impact.

If you want a SciFi story touching many such topics I highly recommend "Seveneves" by Neal Stephenson.

Parameters for 300 km range (200 km STS altitude + downrange)

https://impact.ese.ic.ac.uk/ImpactEarth/cgi-bin/crater.cgi?d...

    Thermal Radiation:

    Time for maximum radiation: 11.5 seconds after impact

    Visible fireball radius: 223 km ( = 138 miles ) 
    The fireball appears 169 times larger than the sun
    Thermal Exposure: 7.72 x 10^9 Joules/m^2
    Duration of Irradiation: 49.7 minutes
    Radiant flux (relative to the sun): 2590

(The physics aren't the same, but just for the sake of comparison: Chicxulub's 4e8 megatons-TNT of energy, at 300 km, is 1/r^2 equivalent to a 4 megaton nuke, at 30 meters).

>(The physics aren't the same, but just for the sake of comparison: Chicxulub's 4e8 megatons-TNT of energy, at 300 km, is 1/r^2 equivalent to a 4 megaton nuke, at 30 meters).

Altitude 300mi is not the same as linear distance to blast 300mi

At 300mi up you could be over a different continent and get a good view and you would probably want to be so that you get a better view from the side.

It would help that Mars has a less dense atmosphere than earth (about 1%), so there’s less stuff to heat. On the other hand ejected material would face less resistance from the atmosphere and thus reach larger heights (even ignoring Mars’ lower gravity)

> I would return 66 million years ago to witness the meteor impact from the safety of a space shuttle.

Don't know how safe you would be. If I remember correctly, there's a theory saying that impact ejecta even shot out into space.

Crazy.

I wonder how they simulate the displacement of water since it's not from how tsunamis usually occur. A lot of water you think would be vaporised into the air and moved with the shockwaves. Plus there is only so much water at the impact site, not an unlimited amount. Given the speed of the impact, would it move as much water? They say when you jump off a bridge, the impact is like hitting cement.

As far as i know, the earth's crust below and around the impact gets displaced by a fair amount. I think the crust acts like a rubber sheet bouncing backwards and forwards. This most likely contributes toward the displacement of water above.

That reminds me, I remember reading some NASA stuff my dad would bring home talking about simulations of impacts. While there are very few on earth there are vast numbers on the moon and other planets.

I think the forces and energies are so large that the fluid dynamics dominate.

I struggle to imagine the impact of 2+ mile high waves.

I’m imagining that much water would scour the land clear pretty severely.

There are a bunch of Coulees in North America, the effect of the water released in a very short time (48 hours) is still visible https://en.wikipedia.org/wiki/Grand_Coulee 18,000 years later. It is one of the most impressive landscapes that I've seen in person (that one, the Grand Canyon and a very large glacier in the North of Canada).

It'd make everything wet, and do some other stuff.

Museum just opened last year in the beach town/cruise port nearby.

https://www.theyucatantimes.com/2022/10/dinosaurs-take-over-...

There needs to be another video from opposite side of the world. And data on how much difference is there in the severity on both sides.

The 2020 paper establishing Chicxulub event as the driving factor of extinction also said that "prolonged eruption of the Deccan traps might have acted as an ameliorating agent" i.e. cancelling the negative effects of asteroid impact.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7382232/

Who needs this when theres the last two seasons of The Expanse?

I found the last two seasons somewhat disappointing. Still a good show, but the first four were a lot stronger. I did go read the books, so I know what happens over the last three books. It's a real shame they didn't have more seasons to cover the Laconia plot, other than to tease it in the last season with the Strange Dogs novella material. The problem with the last two seasons is the heavy focus on Sol politics a full season after the gates were opened and the big alien mystery is left hanging.

The tsunami after the #1 earthquake ever recorded

https://www.youtube.com/watch?v=oeKewmAoBEM

I wish someone make a 3d simulation of the tsunamis and put them in VR. Or even make a survival game out of it. Like a stage in fortnite.

The tsunami was a minor effect from that asteroid - setting the whole planet on fire and releasing a ton of toxic gases in the athmosphere is what did the real damage.

If this were to happen today now much evidence would be find of our current civilisations? Would archeologists be able to figure out our cities?

I get the impression that there might not be any archaeologists left after such an event.

A few humans might survive. If not, there might be other archaeologists, eventually...

Not likely, if we are talking about millions of years.

https://www.cbc.ca/radio/quirks/june-30-2018-a-comet-from-th...

Asking how you could tell if Dinosaurs had a civilization like ours used to be a standard Geology Dept. PhD orals question. Their cities would of course be long long, so that's not a productive search area. The answer is you'd look at the distribution of minerals. If they built cities with skyscrapers they would have had to mine the materials required to make them. There is no evidence the Dinosaurs exploited their available mineral sources but millions of years from now there will still be ample evidence that we did.

Of course this also means that pre-industrial civilizations are completely undetectable after several million years.

Wow, very impressive visualization. Minor editing needed in the bullet point factoids:

The amplitude of the wave animated here reached 1.5 km miles high (0.93 miles) but the initial wave might have reached 4.5 kilometers high (2.8 miles).

Also, I think they could have gone with "1.6 km (1 mile)" or maybe "1.5 km (about 1 mile)" perhaps. Oh well.

So like how much would the sea have retreated? Or would the impact not result in that like a regular tsunami?

Some game engine could do a 3D simulation over real google earth view with current cities?

Humans didn't exist back then. But taking into account how much destruction and change it did to all life on earth, if this event never happened, would we have still evolved into current humans?

mammals existed since 200 million years ago but didn't get a chance to dominate until dinosaurs freed up ecological niches and removed competition

We sometimes mistakenly think history started with the written words we find. But a story travels much further from the past however it is told. And this would be a hell of a flood story.

Are we sure an asteroid killed the dinosaurs? Vulcano erruption leaving the earth in darkness for a prolonged time is another theory.

We are reasonably sure, yes. Significantly more sure since January 2020.

https://en.wikipedia.org/wiki/Cretaceous–Paleogene_extinctio...

https://www.nytimes.com/2020/01/16/science/dinosaurs-extinct...

https://www.science.org/doi/10.1126/science.aay5055

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7382232/

Why can't it be both such big impact could have resulted in a volcanic eruptions.

Or volcanic eruptions were going on prior to the impact. They are implicated in most of the other global extinction events.

What ultimately killed the dinosaurs was their own stupidity, greed, and short-sightedness. If they were smart, they would have developed a good space exploration program and technologies to track potentially dangerous asteroids and adjust their orbits before they collide with Earth. They didn't bother to work to protect their only habitat, so it was rendered uninhabitable, killing almost all of them off. Hopefully, future inhabitants of Earth will learn this lesson in time, but I doubt it.

I mean, we have all those fossil fuels. They must have had them, their names right on them; why didn't they use those?

If only they had listened to Elonis muskasaurus !

Can anyone explain how can it be 20 kilometers in depth and yet Mariana trench is the deepest place on earth 11km ?

The article says:

  > The Chicxulub crater is an impact crater buried underneath the Yucatán Peninsula in Mexico.

So I guess plate techtonics have caused things to shift around such that the crater isn't a hole in the surface now, but is underneath other rock?

Fun fact: If you google "Chicxulub crater" you see an animation of an asteroid crashing.

It was an impact crater. Over millions of years it was filled with sediment, so it's not that deep anymore.

Wasn't this the end of Deep Impact?

No, that was much smaller in comparison. In the movie they managed to break it up so only smaller pieces hit.

RIP Louisiana goddamn

two words here: laser printers!

4 meters*

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