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Asteroid more powerful than 10 billion WWII atomic bombs may have wiped out dinosaurs

An artist’s interpretation of the asteroid impact that wiped out all non-avian dinosaurs. (Image source: NASA)

The asteroid that wiped away dinosaurs from the Earth is estimated to have been equivalent to 10 billion atomic bombs that were used in World War II. The impact of the giant asteroid had triggered massive tsunamis and let to wildfires that were thousands of miles away, according to research led by The University of Texas at Austin.

According to the findings of the research, the asteroid blasted so much sulpher into the Earth’s atmosphere that it led to blocking of the sun rays which ultimately caused global cooling that led to the extinction of dinosaurs.

Scientists have found hard evidence in the hundreds of feet of rocks that filled the impact crater within the first 24 hours after impact, according to the research which got published in the journal Proceedings of the National Academy of Sciences.

The evidence includes bits of charcoal, jumbles of rock brought in by the tsunami s backflow and noticeably absent sulphur. All of these are a part of the rock record which provides the most details into the catastrophic aftermath that ended the dinosaurs, according to Sean Gulick, a research professor at the University of Texas Institute for Geophysics (UTIG) at Jackson School of Geosciences.

Gulick had led the study and co-led the 2016 International Ocean Discovery Program scientific drilling mission which retrieved the rocks from the impact site offshore of the Yucatan Peninsula. The research is built on the previous work that was co-led and led by the Jackson School which described how the crater had formed and how the life recovered quickly at the site of the impact. Over two dozen international scientists contributed to the study.

Most of the material which filled the crater within a few hours of the impact was there at the site of the impact or got swept in by seawater pouring into the crater from the nearby Gulf of Mexico. According to the researchers, 425 feet of material was deposited in a day, which is the highest ever found in the geographical record.

Gulick explained it as a short-lived inferno at a regional level, followed by a long period of global cooling. "We fried them and then we froze them," Gulick said in a statement. "Not all the dinosaurs died that day, but many dinosaurs did."

The researchers found charcoal and a chemical biomarker associated with soil fungi just above layers of sand that showed signs of being deposited by resurging waters.

According to the researchers, the area surrounding the impact crater is full of sulfur-rich rocks. However, there was no sulfur in the core. This, according to the researchers, supports a theory that the asteroid impact had vaporised the sulphur-bearing minerals which were present at the impact site and released it into the planet’s atmosphere.

The scientists estimated that at least 325 billion metric tons would have been released in the atmosphere by the impact of the asteroid. This would have reflected the sunlight away from the planet and caused global cooling. This is around four orders of magnitude greater than the sulphur which was released in the atmosphere during 1883 eruption of Krakatoa that cooled the Earth’s climate by an average of 2.2 degrees Fahrenheit for five years.

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Scientists concluded that though the impact of the asteroid created mass destruction at the regional level, it was the global change of climate which led to the mass extinction of dinosaurs and most other living species on Earth during that time.

"The real killer has got to be atmospheric," Gulick said in the statement. "The only way you get a global mass extinction like this is an atmospheric effect."