Dinosaur-killing asteroid made Earth odor like ‘rotting veg’ in hellish finish for beasts

Experts have revealed how the asteroid that killed the dinosaurs sparked a hellish apocalypse of supersonic winds, acid rain and a foul stench of rotting veg

View 4 Images

A terrifying blow-by-blow account has laid bare the true horror of the asteroid impact that wiped out the dinosaurs, revealing a hellscape of acid rain, supersonic winds and a stench of rotting vegetables. Around 66 million years ago, the world as we know it ended when a six-mile-wide space rock, known as Chicxulub, slammed into what is now Mexico.

While the impact famously signalled the end for the dinosaurs, it also triggered a global catastrophe that saw temperatures plummet and more than half of all species on Earth vanish.

However, in a twist of fate, the apocalypse paved the way for mammals to take over, eventually leading to the rise of humans.

Professor Michael Benton of the University of Bristol and The Open University’s Professor Monica Grady have now mapped out the sights, sounds and smells of the events that unfolded.

Writing for The Conversation, the experts said: “The event triggered instant changes to our planet and its atmosphere and led to the extinction of the dinosaurs and about half Earth’s other species.”

They added: “But what would it have been like to experience such a gargantuan impact? Would you have died or survived? As experts on meteoritics and palaeontology, respectively, we’ve created a detailed timeline, based on decades of research, to take you right there.”

Just 24 hours before the collision, the impact site was a warm 26°C. The asteroid would have been visible in the night sky for a week, but by the final day, it was visible even in broad daylight, appearing like a star growing gradually brighter.

At the moment of impact, a blinding light was followed by a deafening sonic boom as the rock hit the Yucatán Peninsula. Anything in the immediate vicinity was vaporised instantly.

The experts said: “The asteroid is so huge that it almost certainly hits the ground before any living creature near the impact zone has time to run for cover.”

Even those 1,240 miles away would have been killed almost instantly by thermal radiation and supersonic winds.

Within five minutes of the hit, winds equivalent to a Category 5 hurricane flattened everything within a 932-mile radius. Temperatures soared to a blistering 226.85°C as the air filled with superheated steam.

The professors said: “Next come the tidal waves, triggered by the vast quantities of displaced rock and water. These 100-metre mega tsunamis first strike the shores of what is now the Gulf of Mexico.”

Anyone within 1,864 miles who survived the initial blast likely succumbed shortly after to earthquakes, firestorms, or “impact melt” raining from the sky.

An hour after the collision, shockwaves became the least of the survivors’ worries. The experts wrote: “Shockwaves on land and sea are only minor inconveniences compared with the fire that is still radiating down from the sky.”

As a belt of dust circled the globe, the sky began to go dark as far away as Denmark. Within 24 hours, 50-metre-high tsunamis crossed the Atlantic and Pacific, while global wildfires filled the atmosphere with soot.

The experts said: “Trees and plants in general, including phytoplankton, close down as if for winter, unable to photosynthesise. Any animals that rely on warm conditions ultimately hunker down and die.”

By the end of the first week, the planet was plunged into a deep freeze, with temperatures dropping by at least 5°C.

The researchers said: “This means that most of the dinosaurs and other large flying and swimming reptiles probably die from freezing within the course of this first week.”

As if the freezing dark wasn’t enough, storms of corrosive acid rain began to fall. The combination of rotting dead animals, choking smoke and sulphur aerosols meant the entire planet would have carried a revolting stench of decaying veg.

A year later, the sun still hadn’t come out. Temperatures were 15°C lower than before the disaster, and the landscape was littered with the skeletal remains of giants.

Only tiny creatures, like rat-sized mammals and insects hiding in crevices, managed to cling to life. Even a decade later, the Earth remained trapped in a fierce winter with frozen rivers and lakes.

The experts said: “Clearly, there were no humans about at this time – there weren’t even any larger mammals. But given the only species that survived were those that could burrow or live below water, it is unlikely that you could have survived this long.”

Fast forward 66 million years, and the world had finally recovered. While the impact killed off half of all life, it allowed mammals to flourish.

The experts added: “It is salutary to think that without the asteroid collision, primates might never have reached the level we are at today.

“But it is equally salutary to consider that modern humans are causing some of the same changes to the atmosphere that ultimately killed our reptilian forebears and may one day also lead to our own demise.”

For the latest breaking news and stories from across the globe from the Daily Star, sign up for our newsletter by clicking here.