I enjoyed that video when he launched it, but since then I can’t help wonder: “if the damage was so severe, how did any dinos survive and evolve into birds?” I wonder if maybe it’s a more extreme version of events.
What I get reading over the years is on land anything that couldn't crawl into burrow in the ground didn't make it.
I think the answer with birds is they already existed as separate species from dinosaurs.
""Birds evolved from theropod dinosaurs during the Jurassic (around 165–150 million years ago) and their classic small, lightweight, feathered, and winged body plan was pieced together gradually over tens of millions of years of evolution rather than in one burst of innovation. Early birds diversified throughout the Jurassic and Cretaceous, becoming capable fliers with supercharged growth rates, but were decimated at the end-Cretaceous extinction alongside their close dinosaurian relatives.""
So there was a huge variety of bird-like creatures at the time of the strike, and today's birds are descended from the small number of these that survived. Possibly even from a single surviving species.
<pedant> Notice all the grass everywhere in that video. Grass wasn't around until 55 million years ago. The asteroid hit 66 million years ago. </pedant>
(I thought it was kinda neat that grass wasn't a thing for a long time...)
According to wikipedia, grass is now believed to be a bit older:
> Before 2005, fossil findings indicated that grasses evolved around 55 million years ago. Findings of grass-like phytoliths in Cretaceous dinosaur coprolites from the latest Cretaceous (Maastrichtian) aged Lameta Formation of India have pushed this date back to 66 million years ago.[11][12] In 2011, revised dating of the origins of the rice tribe Oryzeae due to findings from the same deposit suggested a date as early as 107 to 129 Mya.[13]
Still, that seems surprisingly recent. Ginkgo trees are almost 3x older.
Did that Tanis theory (guy claimed to have found a former inland lake in North Dakota that experienced tsunamis due to the meteor impact, leaving various interesting fossils) ever go anyplace?
I came across a presentation from geophysicist Mark Richards at the University of Washington, that discusses this. I don't know a whole lot about this stuff, but the information as he presents it seems compelling. Loads of fossilized fish with tektites clogging up their gills.
One of the scariest videos I've ever seen in my life is this asteroid impact simulation: [1]
After watching it I couldn't believe the world wasn't making preventing this sort of a catastrophe a high priority. Instead, if you talk to most people about seriously funding asteroid impact prevention you're likely to be seen as some sort of paranoid nut.
People think they have much bigger things to worry about. Well, it doesn't get much bigger than this.
Priorities are balanced by two factors; probability and time.
And time always (?) matters more.
In other words we worry more about things that may happen today, and tomorrow than what will happen in the next 100 years.
For example the Cascadia fault _will_ slip in the next 100 years (probably) and cause (probably) millions of deaths, and likely make living on the west coast untenable for some generations. But its (almost certainly) not gonna happen today or tomorrow.
By contrast much smaller events affecting "almost no-one", like say missing stop signs leading to traffic fatilities, will use up significant human hours this week.
Which is to say, we prioritise our lives at "human scale" not geologic scale. Small things, small timeliness, not big things on big time lines.
There's also not a lot of point worrying about things we can't really do anything about. When the next asteroid arrives, or when Cascadia slips, there's not a whole lot you can have done to make a difference. (mostly it boils down to "don't be there".)
> the Cascadia fault _will_ slip in the next 100 years (probably) and cause (probably) millions of deaths, and likely make living on the west coast untenable for some generations.
That seems hyperbolic to me. The average interval for Cascade quakes has been 570-590 years. It has been 321 since the last. It could happen in the next 100, but it's a stretch to say that it probably will.
I also think the 'millions of deaths' prediction is overstated by 2 to 3 orders of magnitude. And while a 9.x earthquake would be big, making it untenable to live on the west coast for generations is a pretty wild prediction.
Apologies, in the 100 year time scale I was referring to this [1] - but that is for a "big one (8.0-8.6)" not a "really big one (8.7-9.2)". The risk of a big one is 1 in 3 in the next 50 years, 1 in 10 for the really big one.
So _likely_ 250 till the next big, big one. So who cares right? The very definition of "not my problem". On the up side (referring back to the top of this thread) ELE Asteroids are millions of years apart :)
The predictions I've seen by folks much more capable than me suggest a death toll in the 5-10K range for a magnitude 9 Cascadia quake.
They also say we could lose 10-20% of all the structures. No doubt about it, this would be devastating. It would probably be decades before we fully rebuilt everything. But it certainly wouldn't make the west coast uninhabitable, thought it would likely make it very inconvenient for a few months at least.
As someone who lives on the Cascadia fault (hi from beautiful British Columbia) we do care and we do prepare as much as we can. We build our infrastructure to better withstand earthquakes and replace or remove those that can't. As a community, we are aware, we prepare, the city itself has workshops teaching you to prepare, to show the neighbourhood where you live from this angle and so on.
> and likely make living on the west coast untenable for some generations
My point was that when people wake up in the morning they care more about breakfast than checking the news to see if there was an earthquake. I'm not saying you don't care (at all) but ultimately that the level of caring is crowded out by, well, life.
Alas preparation (as much as you can) is a good thing, but the forces involved, and the sheer scale of the event (assuming a big one of course) will make preparations useful on a personal scale (my house didn't fall on my head, yay) but largely immaterial in the grander scheme of things.
Preparation will save lives. But the impact of the event will change everyone, prepared or not. Infrastructure will vanish, no roads, bridges, harbors, airports, rail. Food distribution, power, water, sanitation will all be off for extended periods of time.
In the long term one can expect large areas of unstable debris, oil and chemical pollution and so on.
Between the earthquake (perhaps a 9) and the tsunami, there's going to be a big mess, over a very large territory.
Regarding the west coast being untenable - mostly that revolves around infrastructure, and the ability to recreate it. Given the impact the event will have on the rest of the country (countries) the ability, or finances, to recreate it will be impaired.
Imagine you wake up tomorrow and Microsoft, Amazon, Apple, Facebook are just "gone". What would the ripple effect on other business be? Would that spark a recession? With respect to New Orleans, Katrina displaced 800 000 people, cost $125 billion, and roughly 10 years to reconstruct. And again, with respect, the cause of the disaster is trivial, and the result small, compared to a factor 9 quake, and 100 ft wave.
Imagine that playing out over the whole west coast, from Vancouver to San-Diego. The impact will be national, not local and it will be a long time before life on the west coast resumes in anything like the scale it is now.
>Priorities are balanced by two factors; probability and time. And time always (?) matters more.
I remember reading a critique of conventional risk analysis about a decade ago that said some things were too big to allow to happen even if the risk of them happening by conventional analysis was too small to make the investment worthwhile.
Then again, investment to mitigate these kinds of risk could lead to profitable advancements even if the original cause does not happen. It's a matter of priorities.
After all, there were many important and also generally useful advancement due to space program.
In my educated opinion, we should focus on climate change first, especially securing cheap food, water and electricity for everyone. Additionally, prepare for the catastrophe that would be 5 C warming since it is likely in our lifetime. The same approaches to survive this lesser ecological problem may prove useful for space travel or terraforming.
I don't particularly care under which budget this research is done as long as it commences.
"When the next asteroid arrives, or when Cascadia slips, there's not a whole lot you can have done to make a difference."
Asteroids can be diverted, given enough warning.[1] There are theoretical proposals for doing so, but its never been tried.
Massive funding of testing, standby spacecraft with asteroid diversion capability, and increasing Earth's early warning system are all realistic things that could be done, were there a political will to do it.
Unfortunately, like COVID, I expect it'll take a devastating asteroid impact that costs millions of lives and trillions of dollars before the Earth wakes up to this threat.
Yeah, the video says diameter of 500km and the asteroid that killed dinosaurs was estimated to be 10-15km, so in terms of mass that's a factor of (500 / 15) ^ 3 = about 37,000.
I think it would depend where we draw the line on Earth's history and the time distribution of these impacts. During the early days of the Solar System huge impacts would have been part of "the old normal", but there's a limit to how many massive rocks there are to go around.
On a side note, I didn't find that video particularly impressive–of course the impact of an asteroid whose diameter is larger than the width of bloody Japan would be apocalyptic! I also found it a bit gratuitous when they showed recognisable landmarks looking a bit damaged when the whole world is lava, and pointless that they talked about the effects "a month" later. What is even "a month", if not even the extremophile archaea survive?
Yeah because it's pretty much impossible. It's unbelievably hard even detecting an incoming asteroid let alone prevent it. See: https://youtu.be/4Wrc4fHSCpw
So making life multiplanetary, what Elon Musk has been saying, is basically the only feasible protection? Not a Musk fanboy but happy that at least something is happening.
Earth after a massive meteor impact will almost certainly be more habitable than Mars on its best day. Every step to make Mars more habitable is much more easily taken to make Earth more habitable in preparation for a massive impact. And Mars might get hit the same way.
Earth with structures designed to withstand Chicxulub will be more habitable than Mars with structures designed to withstand Mars, sure.
However, Earth doesn't have structures designed to withstand Chicxulub, there is no incentive structure to build a substantial number of them and we have no way of testing them even if we had them. Earth without structures designed to withstand Chicxulub is less habitable than Mars during Chicxulub.
And without a substantial atmosphere Mars is much less vulnerable to Chicxulub than Earth is, and the structures on Mars would mitigate it much better than Earth's structures mitigate it here on Earth.
The problem with this line of thinking is that first we'd have to be elsewhere to survive the initial destruction of this magnitude, which would be a huge tsunami and cloud of dust that would stay in the atmosphere for years. There are ways to build bunkers that are capable of withstanding this kind of disaster (we'd have at least a month of warning), but not yet a way to keep a biome running.
Therefore, (and considering climate change, priority) research should be focused on maintaining large scale artificial biomes for now. We'll need that for space travel and colonization anyway.
The Earth atmosphere you describe is more life sustaining than Mars. <- that is a period.
The problem of survival after a massive impact on Earth is more readily solved than survival on Mars. Indeed survival on the Moon is easier simply for logistics.
If you want go to Mars. I will stay here. Natural selection will work its magic either way. My bet is on six billion years of priors. Not Mr. Musks Tweets.
Did you watch the video pmoriarty linked? If that is a valid model of the aftermath of a very large asteroid collision, then no, you would not be better off here than on Mars. It would literally be hotter than Venus for an extended period of time, if what they are saying is correct.
It's probably not a good model as that's an absolute giant as asteroids go. The one at the end of the Cretacous would have had 1/10000 or something of this one's mass, and we consider that a planet killer already. I think a 500km monster really is exceedingly unlikely, there are a lot less of those and getting hurled in our direction probably gets way harder, too, at that size. More realistic scenarios with smaller (city-scale) bolides would be absolutely devastating, too, but still way more survivable.
That was an extremely rare event that has only happened once in the history of our planet when the solar system was young. It's incredibly unlikely to happen in future, it's even less likely to happen by the time we've moved to Mars because the sun has expanded enough to make earth like Venus anyway.
The structures we build on Mars will be made to anticipate the Martian conditions. Most of the structures we have here on earth were not built to anticipate an asteroid impact.
Usually it is known beforehand when an asteroid will collide. We might not manage to build structures quickly enough to save all humans, and the resulting scramble for the few spots in the bunkers might destroy them. There also won't be any time to test the design and subsequently improve it. On Mars we have plenty of opportunity to measure the environment. Even if the worst happens, we can still repopulate the colony from earth, as long as our society is not being scared by such failures and stops manned Martian efforts completely.
> Yeah, but during the impact we need to be somewhere else.
Bunkers should be fine, the deep sea may be fine, moon will pretty much certainly be fine, high orbits should be fine as well. If you can manage to be on the other side of the planet, surviving the impact should be quite manageable if you have the kind of resources that can build a deep, shock-resistant bunker, and you should be able to do that much, much easier than build Mars colonies that are independent enough for this, and large enough to not just save a hundred people.
After the initial effects wear off, you're probably facing conditions topside that are absolutely brutal, but still way less so than Mars with its toxic soil and dust, thin, useless atmosphere, supercold temperatures, very low gravity, scarcity of easily-accessible nitrogen (let alone easily accessible metals), high radiation environment, ...
Basically, if you can set up a naval nuclear reactor and some lighting and greenhouses, you should be able to get food production going in spite of any realistic asteroid winter, the air will still be breathable, the soils will still work for agriculture, ... and you can make use of all that survives of our artifacts and civilization, which should be a lot. Mining former cities for resources could be a big jump-start.
Because the skillset and technology required for asteroid intercept is quite different to anthropogenic climate change remediation, and we can and should do both to take full advantage of the interests and aptitudes of each generation?
Fortunately we actually are doing quite a lot about asteroids, since our sky coverage of possible planet-killers is good enough to have reasonable confidence we'd get some warning. The rest is going to be a product of cheap commercial rocketry.
At least with an impact that size, you're dead in under a day, and it happens instantly. The Chicxulub asteroid is immensely more scary because many parts of the world would descend into a The Road type of situation, where death could be drawn out.
When I see things like these, I'm always wondering why the impactor is almost always styled with red glowing lava, like in some bad Sci-Fi movie. Where would that heat come from?
Is the idea of some cold and dark rock hitting fast not dramatic enough?
Realistically, there's no way we could stop a 500km diameter asteroid from impacting earth no matter how much we prepare. Mankind's best bet to survive that case is to colonize another planet.
"Realistically, there's no way we could stop a 500km diameter asteroid from impacting earth no matter how much we prepare."
I'm not convinced. See [1].
Anyway, it doesn't have to be that huge in order to completely devastate the Earth. So even if it was impossible to stop one that large then it would still make sense to prepare to stop smaller ones.
I don't see anything in that article to suggest that we have (or in the forseeable future will have) the technology to deflect an asteroid the size of the one in the video you linked. Nuclear standoff was one of the most promising methods they discussed... with an example using a 100 megaton nuclear device to deflect a 1.4km diameter asteroid. A 500km asteroid is 45 million times more massive.
Yes, we should still develop the technology to deflect smaller asteroids, but my point was that we're not going able to deflect the earth shattering asteroid like the one in the video so if we really want to make mankind "asteroid proof", then we need a second earth.
The 100 megaton example was for a deflection of an asteroid for which we have 18 months of warning.
With much larger asteroids we could have significantly more warning time, and so the distance that asteroid would have to be deflected could be much smaller to have it eventually miss the Earth.
Other dynamics would probably come in to play too, such as the gravity of other planets in the solar system. Depending on where the asteroid was, where it would be passing through, its mass and velocity, and how much time we had to deflect it, I think even something as large as that might be deflectable.
Also if significant funding and attention was given to this problem, and people realized that the existence of life on Earth depended on it, I'm sure there'd be a lot of innovation, resulting in all sorts of other ideas and technologies that we haven't thought of yet.
It's premature to throw up our hands and give up on preventing this incredibly dire threat without giving it a much more serious try than we've done so far.
Also if significant funding and attention was given to this problem, and people realized that the existence of life on Earth depended on it, I'm sure there'd be a lot of innovation, resulting in all sorts of other ideas and technologies that we haven't thought of yet.
Did you just wake up for a coma or something? Recent history has shown that when faced with a life-threatening disaster, half of this country is going to deny that there's a threat at all and an expensive project to ward off a threat that's decades away won't get funded until it's too late.
