Asteroid That Killed The Dinosaurs: Likely Origin And What We Know About The Famous Space Rock

The asteroid that struck Earth 65 million years ago was large enough to cause global devastation.

It slammed into the Yucatán Peninsula of Mexico, creating a massive crater that is now known as the Chicxulub Crater.

Asteroid That Killed The Dinosaurs: Likely Origin And What We Know About The Famous Space Rock

Scientists believe the impact triggered a mass extinction event that wiped out the majority of life on our planet.

But what do we know about this famous space rock and about where exactly it came from? Read on for a deep delve into the ancient past!

How Big Was The Asteroid That Killed The Dinosaurs?

Chicxulub, the asteroid that killed the dinosaurs, was about 7.5 miles (12 kilometers) wide and was traveling about 27,000 mph (43,000 km/h) when it impacted planet earth.

To put this into perspective, it would have been around the size of Manhattan!

If you find it hard to imagine that, another comparison that is often given is Mount Everest.

The Chicxulub impactor created a scar 93 miles wide (180km) and 12 miles deep on the planet’s surface.

Who Discovered The Impact Crater?

In the late 1970s, two geologists, Antonio Camargo and Glen Penfield, working in the area of the Yucatan Peninsula, discovered an unusual circular feature.

They were studying the region because they suspected there might be some sort of buried structure beneath the ground.

But their initial findings didn’t make sense. There weren’t any volcanoes in the area, so how could such a huge hole exist?

If it wasn’t caused by volcanic activity, then what?

It wasn’t until 1990 that scientists realized that the Chicxulub crater was the result of an impact event. 

What Is The K-Pg Boundary?

The name “K-Pg” stands for “Cretaceous–Paleogene.” This boundary marks the point at which the Cretaceous Period ended, and the Paleogene began.

The Cretaceous period lasted approximately 66 million years, and the Paleogene lasted approximately 23 million years.

At the end of the Cretaceous Period, the dinosaurs went extinct.

What Evidence Shows That Chicxulub Is An Impact Crater?

Asteroid That Killed The Dinosaurs: Likely Origin And What We Know About The Famous Space Rock

There are many lines of evidence suggesting that the Chicxulub impact occurred.

First of all, the location of the impact site is consistent with the estimated path of the asteroid.

Secondly, the crater itself contains features that are typical of an impact crater. 

For example, the geochemical evidence shows a layer of iridium in the soil layers. Iridium is a rare element only found in meteorites.

The iridium levels match those expected from a collision between a body of that size and the earth.

In 1980, Luis Walter Alvarez and his son Walter Alvarez published a paper showing that the chemical composition of the rocks surrounding the impact site matched the chemical signature of a meteorite.

The Alvarez family had previously studied meteorites and concluded that the Chicxulub impactor originated from outer space.

In addition, the Alvarez team also analyzed the sedimentary layers near the impact site and found that the strata had formed after the impact.

This indicated that the impact happened very quickly, within a few hours or days.

What Happened After The Impact?

The force behind the asteroid impact is thought to have released a billion times more energy than that released by the atomic bomb dropped on Hiroshima, Japan, at the end of the Second World War.

As well as the devastation caused by such an impact itself, it also resulted in drastic climate change, which contributed to the extinction of the dinosaurs.

A huge dust cloud blocked the sun for many years and stifled life.

Wildfires ate up huge expanses of forest, and the atmosphere became extremely toxic due to the release of sulfur dioxide gas.

The air also became very acidic, causing the oceans to become corrosive. These conditions led to the death of most marine organisms.

In addition, the impact generated a shock wave that traveled through the Earth’s crust and heated up the mantle below.

This heat melted rocks and caused earthquakes.

When the asteroid struck, it released enough energy to cause global devastation.

The impact resulted in a gigantic tidal wave, earthquakes, and volcanic eruptions. Many animals died as well.

For example, the sea level rose 18 feet (5 meters), flooding coastal regions.

Some estimates suggest that more than 90 percent of animal species living during the time of the impact became extinct.

What Type Of Asteroid Was The Chicxulub Impactor?

Most scientists believe the Chicxulub impactor was a solid mass that broke off from a larger asteroid.

It is thought to have had a carbonaceous Chondrite composition.

Carbonaceous chondrites are asteroids made mostly of carbon and other elements.

They are believed to be similar to the material that makes up comets. However, they do not contain water ice.

Where Did The Asteroid Come From?

Asteroid That Killed The Dinosaurs: Likely Origin And What We Know About The Famous Space Rock

Scientists think that the dinosaur-killing asteroid that collided with the Earth originated from the asteroid belt between Mars and Jupiter.

The asteroid belt is an asteroid population of millions of objects orbiting the Sun between Mars and Jupiter.

Scientists estimate that there are tens of thousands of asteroids larger than 1 kilometer (0.6 miles) across in this region.

Most of these large bodies are called Main Belt Asteroids. They are largely made up of combinations of rock, ice, minerals and silica.

Any one of these asteroids would prove a catastrophic object if it came into contact with Earth.

When the dinosaur-killing asteroid entered the solar system, its path took it near Jupiter.

Because Jupiter has a strong gravitational pull, the asteroid changed course slightly and headed toward the Earth.

Once it made contact with the Earth, the huge chunk of space rock slammed into our planet at high speed.

What Happened To The Dinosaur-Killing Asteroid?

The enormous chunk of space rock is thought to have vaporized into millions of pieces when it hit the earth.

These fragments then vaporized into clouds of debris, which were carried by winds around the globe.

When the dust settled, some of the particles formed new meteorites.

Some of the debris landed on land and created mountains and volcanoes.

Others fell back down to earth and buried themselves deep underground.

Still, others remained suspended in the upper atmosphere where they could not escape.

These “stratospheric” meteors eventually burned up in the atmosphere.

Had the impact occurred moments later, the dinosaur killer may not have been nearly as devastating.

If it had hit deeper water rather than the shallow coastal waters of the Mexican peninsula, there would have been far less vaporized rock, and the climate devastation would have been greatly reduced.

How Much Energy Was Released By The Impact?

According to calculations based on data gathered from the crater left behind, the asteroid released approximately 10 billion megatons of energy.

As previously mentioned, this amount of energy is equivalent to roughly 100 million Hiroshima bombs.

Why Did Birds Survive The Asteroid Impact?

The only prehistoric creatures to survive the impact were avian dinosaurs. All non-avian dinosaurs died out.

This is mainly thought to be because birds had bigger brains, smaller sizes, the ability to consume a wider selection of foods, and the crucial skill of flying.

It was a combination of these factors that ultimately may have helped birds survive the last mass extinction and outlive the age of dinosaurs.

Final Thoughts

The asteroid that ended the existence of all nonavian dinosaurs on planet earth created the second-largest impact crater.

The largest is the Vredefort crater, which has an estimated diameter of 300 kilometers. This is twice as big as the Chicxulub crater!

Vredefort (located in Free State, South Africa) was created approximately 2 billion years ago, and who knows when the next asteroid will pay us a visit!?

Gordon Watts