00:00The last 24 hours of the dinosaurs. 66 million years ago, an asteroid the size of Mount Everest,
00:06denser, heavier, more massive, struck at 20 kilometers per second into a shallow sea near
00:10the Yucatan Peninsula, Mexico. The crater, still buried, stretches 180 kilometers across.
00:16But the most unsettling fact isn't the crater's size. It's this, death did not arrive all at once.
00:22It came in waves. Fast first, then slow. Near first, then far.
00:28Where you stood decided which killer found you first. So what happened in that exact moment of
00:33impact? Near the impact point, everything unfolded in a single second. The energy released, model's
00:39estimate, equaled tens of nuclear bombs detonating at once. Rock vaporized instantly. A fireball hotter
00:46than the surface of the sun expanded across hundreds of kilometers. Inside that zone, there was no room
00:51for survival. Everything was obliterated. But could dinosaurs thousands of kilometers away live?
00:57The impact's energy, on touching the ground, split into several waves at different speeds.
01:02Seismic waves raced underground at kilometers per second, reaching hundreds, even thousands of
01:07kilometers away, triggering landslides and violent sloshing of water. In the Tannis formation, North
01:12Dakota, researchers found water disturbance lining up exactly with the impact. At the same time,
01:17a giant airblast shockwave pushed outward at over a thousand kilometers per hour. Life nearby was
01:22crushed by extreme air pressure. Farther away, weaker, but still able to devastate the land.
01:28And hiding behind a hill, or deep in a burrow, wasn't necessarily safe.
01:32Because between 10 minutes and an hour after impact, a new threat rained down from the sky.
01:37The impact hurled billions of vaporized rock fragments into space.
01:40As they fell back to Earth, friction with the atmosphere generated extreme heat, a thermal
01:45pulse raining from above. Research suggests this thermal pulse may have ignited forest fires
01:50on a near-global scale. Life exposed on the surface faced lethal heat. But life shielded by terrain,
01:56underwater, or buried underground, absorbed far less. That difference became one of the key
02:01reasons some species survived. The first hour passed. The slowest force had only just left the Gulf
02:07of Mexico. The impact shoved a colossal wall of seawater. As the tsunami raced outward,
02:12its wave height dropped, but the total energy was enormous. Models estimate it was roughly 10,000 times
02:18the 2004 Indian Ocean tsunami. At near jet speed, it crossed the Gulf of Mexico within an hour. Within a
02:25day, it swept across both the Pacific and the Atlantic. And in Antarctic sediment, researchers found
02:30mass marine fossils dying at that exact time. Even the most remote places could not escape.
02:35When the 24th hour ended, the creatures that survived day 1, had they won? Not at all. Day 1 only
02:42killed
02:42the life that failed to hide. The true extinction unfolded after that first day. The impact blasted
02:48dust and aerosols into the atmosphere, dimming the sunlight. Earth entered a period scientists call,
02:53impact winter. Light faded. Temperatures dropped. Photosynthesis plunged. Herbivores lost their food.
03:01Then predators lost their prey. The entire food chain collapsed, layer by layer, from the bottom
03:07up. This catastrophe lasted years, or more than a decade. So why did some animals live? Because
03:13Earth was not covered by one uniform blanket of death. Small animals needed less food, and had a
03:18better chance of surviving. Animals that lived underground escaped the deadliest heat and shock
03:23wave of day 1. Omnivores and scavengers still had many options after the food chain broke. And creatures
03:29able to hibernate, or slow their metabolism, bought precious extra time. That is why some birds,
03:34reptiles, and small mammals survived. Birth lost more than 75% of its species. But the survivors filled
03:41the empty niches the dinosaurs left behind. Humans, we are descendants of one of those survivors.
03:47That asteroid did not kill every dinosaur in a single stroke. It turned its kinetic energy into waves
03:52of disasters, arriving at different speeds, reaching every corner of the planet. Then it made the sky and the
03:58food chain the final two checkpoints. Day 1 decided who could hide. And the world that followed decided
04:04who could keep on living.
