Scientists have revealed information about the impact of a large asteroid that hit the US 35 million years ago.
The asteroid, which is between three and five miles wide, created a large noise about 25 kilometers in the area that is now under the Chesapeake Bay, located in the southern end of Northampton County near Cape Charles. Virginia.
Although slightly smaller than the event that killed the dinosaurs 66 million years ago, researchers expected it to change the global climate in the same way.
Instead, they found that ‘our world seems to be going on as usual,’ according to a study co-authored by Bridget Wade of University College. London (UCL).
In addition, the researchers discovered that another large asteroid collided with the current one Russia 25,000 years ago and only briefly affected the Earth’s climate.
The crater left a 60-kilometer-long crater – known today as the Popigai crater – northern Siberia.
These two asteroid impacts created the world’s fourth and fifth craters, however, did not trigger any climate change over the next 150,000 years, the researchers said. he finished.
‘However, our study did not change over short periods of decades or hundreds of years, as the samples were every 11,000 years,’ Wade explained.
‘In human time, the impact of these asteroids would be catastrophic. If they were to cause a great danger with a tsunami, there would be a widespread fire, and a great deal of dust would be sent up into the air, blocking out the sunlight.’
About 35 million years ago, a large asteroid crashed into the ocean off the east coast of North America, but it did not cause climate change (STOCK)
The asteroid, between three and five miles wide, created a large 25-mile crater that lies beneath the Chesapeake Bay, an area located at the southern end of Northampton County near Cape Charles, Virginia.
Evidence of an asteroid impact was found in tiny silica droplets, which look like tiny glass balls.
These formations were created by the intense heat released as asteroids impact rocks.
The team determined what Earth’s climate looked like after an asteroid impact by analyzing the carbon and oxygen isotopes in more than 1,500 fossils of shelled, single-celled organisms called foraminifera.
Marine organisms lived near the ocean or on the ocean floor between 35.5 and 35.9 million years ago, and it was evidence of the warming of the world’s oceans at that time.
The remains were found buried within 10 feet of rock drilled under the Gulf of Mexico by the Deep Sea Drilling Project.
The researchers discovered isotope changes 100,000 years before the impact of two asteroids caused the oceans to warm by 3.6 degrees Fahrenheit, and the deep ocean to cool by 1.8 degrees Fahrenheit.
But they found no evidence of any climate change during or after the crisis.
Another great climate that hit the land that is now called Russia 25,000 years ago, did not disturb the climate for a short time.
“What’s interesting about our results is that there was no real change in outcomes,” Wade said in the paper words.
‘We expected the isotope to shift in one direction or the other, indicating hot or cold water, but this did not happen.’
The researchers published their findings in the journal Communications Earth & Environment today.
The isotope samples collected were over 11,000 years old, so they don’t show short-term impacts from large asteroids, which would have been “catastrophic” on the human time scale, Wade said.
The Chicxulub impact, for example, caused climate change at a moderate rate in less than 25 years. But it was so extreme that it caused the extinction of the dinosaurs.
“So we still need to know what’s coming and provide funding to help prevent future disasters,” Wade said.
NASA’s Planetary Defense Coordination Office (PDCO) is developing strategies and policies to avoid catastrophic asteroid collisions.
Evidence of an asteroid impact was found in tiny silica droplets, which look like tiny glass balls. These formations were created by the intense heat released as asteroids impact rocks
PDCO’s main mission is to find, track and better understand asteroids that could pose a threat to Earth. But it also launched the Double Asteroid Redirection Test (DART) mission in November 2021.
The mission sent a spacecraft to Earth’s asteroid Dimorphos to change its course — a technique NASA may one day use to save Earth from an incoming asteroid.
Although Wade and Cheng’s research showed how the impact was affected, they created a more accurate time frame for climate change, as previous research used samples that were older than 11,000 years.
In addition, the use of fossils that lived on the bottom of the deep oceans provided a complete picture of how the oceans reacted to the asteroid impact.
‘It was interesting to read the Earth’s climate history from the chemistry preserved in microfossils,’ said Cheng.
