One of the greatest illusions in life is continuity.
66 million years ago, the continuity of the dinosaurs had been going on for around
165 million years already - and it didn’t seem this would change any time
soon. The world was warm, and pleasant, and most of the land was covered with lush forests
and an incredible diversity of trees, flowers, ferns and trillions of critters.
Dinosaurs were ubiquitous and had diversified into hundreds of species of all shapes and sizes.
Titanosaurs, large gentle giants shared the world with famous beasts like Tyrannosaurus rex
or Edmontosaurus. Pectinodon hunted in the undergrowth while Edmontosaurus
wandered coastlines and swamps. An ancient paradise, a world of plenty, full of life.
66 million years ago, maybe on a Tuesday afternoon, life was the same as it had
been the day before or a thousand years before or pretty much a million years before. Things
were good for our feathered dinosaur buddies. Until a tiny, tiny detail in the sky changed.
If there were dinosaurs watching the stars, one night they may have noticed the appearance of a
new star. A tiny dot, that for many weeks slowly became bigger and brighter. Until one fateful day,
it looked like another, small moon in the night sky. And then it faded from sight as
it dipped into earth’s shadow. For a few more hours the illusion of continuity was upheld.
Until it was not anymore. In the morning the object suddenly appears again.
Now almost as large as the sun in the sky and growing every moment,
heading for the coast near the Yucatan Peninsula. It takes the
asteroid only two seconds to pass through the thin layer between space and the ground
to make contact. As it enters the atmosphere at almost 60 times the speed of sound...
Let us stop time.
Here we see the unnamed asteroid about to commit specicide.
Larger than Mount Everest, it reaches from the ocean
high into the atmosphere, higher than passenger planes would fly millions of years later.
At this moment the world was one way. In a fraction of a second
it would be fundamentally different. Let us make the transition.
As the asteroid hits the shallow ocean and the bedrock below
the energy of billions of nuclear weapons is released all at once as the asteroid vaporizes.
A flash of light illuminates the sky as an eerie bright white sphere grows over
the Gulf of Mexico . Bedrock, melts into seething hot plasma at tens of thousands
of degrees celsius. The thermal radiation from the explosion travels at the speed of light and
immediately burns everything within a radius of about 1500 kilometers. while the energy
from the impact pushes so hard against earth’s crust that it loses all strength and flows away
from the impact site like a liquid, creating a hole 25 kilometers deep and 100 kilometers wide.
The ocean is pushed back for hundreds of kilometers, like when a kid jumps into a puddle.
As the crust bounces back, melted and flowing crust forms a temporary mountain stretching
10 kilometers into the sky.. An incredible amount of material is blasted into the higher atmosphere
or even out into space, as much as 60 times the original mass of the asteroid.
The violence of the strike is felt everywhere on earth within minutes.
A magnitude 11 earthquake,, maybe the most powerful quake any living thing has ever witnessed
in billions of years. It is so insanely strong that in India it might have shaken gigantic lava
fields and causes volcanic eruptions that would last for 30,000 years and cover half
of the indian subcontinent with lava. Even on the side of earth opposite the impact,
the ground still moved by several meters. Nobody would sleep through this day.
The gigantic explosion crashes against the atmosphere with unprecedented violence and causes
a shockwave that reaches speeds of more than 1,000 kilometers per hour near the site of impact,
similar to the hyper hurricanes on gas giants like Neptune. In middle America, basically any soil,
vegetation or animal is just shredded into pieces and catapulted thousands of km away.
Now the formally displaced oceans return. As the temporary mountain at the site of impact
collapses, a ring of tsunamis as high as one kilometer, enough to cover all skyscrapers
humans would ever build, heads in all directions. As they crash into the coasts of the continents
surrounding the impact, they will drown thousands of kilometers of coastline.
15 hours later some of the waves that get refracted around South America
will still tower as much as 100 meters into the sky.
But we still have not talked about the worst thing yet.
A lot of the debris yeeted into space will orbit earth for thousands of years, some hit the moon or
even Mars. But most of it comes right back. When things fall through the atmosphere at such speeds
they get very hot, like hundreds of degrees hot. And this happens to millions of tons of
material everywhere. This rapidly heats up the atmosphere to insane temperatures. We don’t know
exactly how hot it got or how long this heat shock lasted but there are two ideas here.
Either the air was heated to hundreds of degrees, for a few minutes. Or to thousands of degrees, for
around one minute. In any case, the air becomes as hot as the inside of an industrial oven. How bad
the global effects of this were is contested but if enough heat reached the surface a lot of plants
and animals would have died very quickly if they couldn’t bury themselves or escape into caves.
The heat together with raining debris also may have ignited material on forest floors
and sparked wildfires as the earth rotated under the searing hot plume. In a few hours
massive wildfires were probably burning around the globe. Some of them may have
lasted for months and turned earth into a horrifying hot hell-ish version of itself.
As the day of the impact draws to an end, many of the dinosaurs are already dead,
but the worst is still to come.
The gigantic plume of vaporized material reaches the upper atmosphere and spreads around the whole
globe. Together with the soot from the burning planet and the aerosols generated at impact, the
planet sinks into a deep darkness, with only the remaining raging fires illuminating the scenery.
Whatever plants survive the firstorms will now be starved for sunlight as global
photosynthesis is temporarily shut down. Within days temperatures crash as much as 25° celsius.
The oceans were especially hit hard. The lack of sunlight killed over 90% of plankton
which form the basis of the food web of marine life. Ultimately this would
kill off the large marine reptiles and ammonites that used to dominate the seas.
The biosphere the survivors now find themselves in is like an alien landscape. Ash,
debris and the burned remains of the formerly lush and blooming life
cover the ground, the sky is dark and it is cold and fresh food is scarce, while fungi thrive.
For months and years the planet will be a hostile and deadly place. The sudden global winter
will last for decades. At least 75% of all species on earth will just vanish from existence.
And so, as the day ends, the world is suddenly different. The continuity that
went on for millions of years is no more. The Era of the dinosaurs is over. Just like that.
Eventually, from the ashes of the old world, survivors emerged. Birds that are the direct
descendents of the dinosaurs and mammals that would eventually become the dominant animals on
the planet. Without the Asteroid, who knows what life on earth would look like today.
Without the sudden disruption of dinosaur continuity, that completely changed the
planet and all life on it, we might have never had the opportunity to become what we are today.
It is not clear how long the Human Era will last. So far modern humans have been around for 0.1% of
the time the dinosaurs were. And in this short amount of time we’ve achieved impressive feats,
from making the world our own, to reaching space and splitting the atom. Yet our future
and our long-term survival is not a given. If we are not careful, it could end in an instant,
like the Age of the Dinosaurs ended. But in contrast to them,
we know that our continuity is fragile, even if it doesn’t feel like it. We can be prepared
and be vigilant and hopeful. If we are lucky, our journey will go on for a long, long time.
Speaking of journeys, we want to address something in the spirit of transparency. Kurzgesagt has
changed in the last two years: We’ve become more than a youtube channel or animation studio
and now also run a paper shop that sells hundreds of thousands of calendars, posters and notebooks.
It's not a happy accident – many of us have a background in graphic design. Paper products
are our roots and we actually started out creating posters, books and print infographics.
We love that you can touch them, smell them, nerd about small details and printing techniques.
Just like the channel, we started small and without great ambition. Step by step, we found
the right printers and papers, learned about shipping and expanded our shop. We put a huge
amount of research, love and hours into it because this is the only way we know how to do things.
We don’t just want to make generic merch but things that fit our mission of making science
exciting and creating beautiful things. Things that persist and are made with high quality and
love. Our shop gives us another outlet to do this and as a nice side effect, has turned into
our main source of income for everything we do on this channel. Which also keeps us independent and
our video free for everyone. So we want to build further on that and create more things that last.
We just started a new notebook line called Pocket Log that we will expand on in the future. The
first edition is a dinosaur themed collection that will hopefully serve a future paleontologist well.
There are loads of plans for sciency stuff, more journals and calendars and infographics!
Let us know what you would like us to make, for your room, kids, classrooms and yourself.
In the end the things we do work because you like them, and because you enable us
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Thank you so much for that. We are looking forward to making fun sciency stuff for you,
no matter if it will be a video, a poster or something else entirely. Thank you for watching.