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  

to put thousands of hours into videos and  hundreds of hours into posters and journals.  

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.