It is well known that the reign of the dinosaurs came to an end when a giant asteroid crashed into Earth 66 million years ago.
But a new study suggests that this huge asteroid was not alone.
Scientists at Heriot Watt University have discovered evidence that a second devastating space rock crashed into Earth that same year.
This second asteroid measured about 500 meters (1,640 feet) across and hit Earth just off the coast of the Republic of Guinea in West Africa.
“The closest we humans have come to seeing something like this was the Tunguska event of 1908, when a 50-metre asteroid entered the Earth’s atmosphere and exploded in the skies over Siberia,” said Dr Uisdean Nicholson. , who led the study.
It is well known that the reign of the dinosaurs came to an end when a giant asteroid crashed into Earth 66 million years ago. But a new study suggests that this huge asteroid was not alone (file image)
The first evidence of this second asteroid was discovered in 2022, while Dr. Nicholson and his team were studying seismic reflection data from the seafloor of the Atlantic Ocean.
The data revealed a depression measuring nearly five miles (9 km) deep, which the team suspected could be an asteroid impact crater.
Now, researchers have taken new high-resolution 3D seismic images of the depression, which have confirmed their suspicions.
The crater has been named Nadir Crater and was excavated when an asteroid hit Earth about 66 million years ago, the same age as the asteroid that killed the dinosaurs.
“There are around 20 confirmed marine craters around the world, and none of them have been captured in such close detail. “It’s exquisite,” said Dr. Nicholson.
Now, researchers have taken new high-resolution 3D seismic images of the depression, which have confirmed their suspicions.
Scientists at Heriot Watt University have discovered evidence that a second devastating space rock crashed into Earth in the same year as the one that wiped out the dinosaurs.
‘Surface craters are usually heavily eroded and we can only see what is exposed, while craters on other planetary bodies typically only show the surface expression.
“This data allows us to image the crater in three dimensions and remove layers of sedimentary rock to observe the crater at all levels.”
In 2022, researchers suggested the asteroid would be about 400 meters wide.
However, new images confirm that it was even larger than this.
Dr Nicholson said: “We now think it was between 450 and 500m wide, due to the larger size of the crater, as shown by the 3D data.
«We can say that it occurred between 20 and 40 degrees to the northeast, due to the spiral ridges generated by the thrust that surround the central peak of the crater; These only form after a low angle oblique impact.
“And we think it would have hit Earth at about 20 kilometers per second, or 72,000 kilometers per hour, although we have yet to confirm this with a new set of impact models.”
This second asteroid measured about 500 meters (1,640 feet) across and hit Earth just off the coast of the Republic of Guinea in West Africa (Nadir Crater, pictured).
Based on the data, scientists have created a timeline of what they believe happened: from the initial collision to a tsunami more than 800 meters high that would have crossed the Atlantic Ocean.
“Following the impact and the formation of the central uplift, soft sediments surrounding the crater flowed to the evacuated crater floor, creating a visible ‘rim’,” Dr Nicholson explained.
“The earthquake caused by the impact appears to have liquefied sediments under the seafloor across the plateau, causing faults to form beneath the seafloor.
‘The impact was also associated with large landslides as the plateau margin collapsed beneath the ocean.
“In addition, we see evidence of a train of tsunami waves moving away from the crater and then returning toward the crater, with large resurgence scars preserving evidence of this catastrophic event.”
While it’s been 116 years since an asteroid like this was seen, it likely won’t be long before another huge space rock hits our planet, according to NASA.
The US space agency predicts that the asteroid Bennu has a one in 2,700 chance of crashing into Earth on September 24, 2182.