During the same era, a second, smaller space rock smashed into the sea off the coast of West Africa and formed a large crater, the BBC reported.
Scientists say it was a "catastrophic event" that triggered a tsunami at least 800m high in the Atlantic Ocean.
Dr Wisdeen Nicholson of Heriot-Watt University first discovered the Nadir crater in 2022, but a cloud of uncertainty hangs over how it formed.
Now, Dr Nicholson and his colleagues are certain that the 9-kilometre depression was caused by an asteroid that slammed into the seabed.
They cannot date the event precisely, nor say whether it occurred before or after the asteroid left Mexico's 180km-wide Chicxulub crater. This asteroid ended the age of the dinosaurs.
But they argue that the smaller rock also came at the end of the Cretaceous period when they died out. When it crashed into the Earth's atmosphere, it formed a fireball.
"Imagine the asteroid has hit Glasgow and you're in Edinburgh, about 50km away. The fireball would be about 24 times bigger than the Sun in the sky - enough to set Edinburgh's trees and plants on fire," Dr Nicholson said.
An extremely loud air blast followed, then seismic tremors measuring 7 on the Richter scale.
Huge amounts of water are likely to have left the seabed and later rushed back down, creating unique footprints on the floor.
It is unusual for such large asteroids to crash out of the solar system on their way to our planet within a short time of each other.
But researchers don't know why two of them hit Earth close together.
The asteroid that created the Nadir crater is about 450-500 meters wide and scientists believe it slammed into Earth at about 72,000 km/h.
The closest such event humans have come to was the Tunguska event in 1908, when a 50-metre asteroid exploded in the sky over Siberia.
The asteroid, Nadir, was the size of Bennu, which is currently the most dangerous object orbiting near Earth.
According to NASA scientists, the most likely date that "Bennu" could collide with Earth is September 24, 2182. But that's still only a 1 in 2,700 chance.
There has never been an asteroid impact of this size in human history. Scientists usually have to study eroded craters on Earth or images of craters on other planets.
To better understand the Nadir crater, Dr. Nicholson and his team analyzed high-resolution 3D data from a geophysical company called TGS.
Most of the craters had eroded, but this one was well preserved, meaning the scientists could look deeper into the rock levels.
"It's the first time we've been able to see inside a crater like this - it's really exciting," Dr Nicholson said. He noted that there are only 20 sea craters in the world, but none of them have been studied in such detail. | BGNES
