Asteroid that killed dinosaurs 'hit Earth at deadliest possible angle'

Asteroid That Sealed The Dinosaurs' Fate Hit Earth At “Deadliest Possible” Angle

The impact vaporized billions of tons of sulfur, the team estimates, which blocked incoming sunlight and effectively plunged the Earth into a nuclear winter that killed 75% of life on the planet.

Chicxulub is also thought to have triggered an natural disaster whose seismic waves reached Tanis - the fossil site 3,000 km (1,864 miles) away in North Dakota where definitive evidence of the asteroid's devastating impact was uncovered - in just 13 minutes.

The findings were published today (May 27) in the journal Nature Communications.

The fearsome event that exterminated some three-quarters of all life on Earth was especially deadly thanks to the asteroid's flight path, according to researchers at Imperial College London, who ran 3D simulations of the Chicxulub impact to better understand its apocalyptic aftermath.

'The asteroid strike unleashed an incredible amount of climate-changing gases into the atmosphere - triggering a chain of events that led to the extinction of the dinosaurs, ' said Dr Collins.

"The Chicxulub impact was a very bad day for the dinosaurs", Collins said, adding that the new research showed it was "even worse" than had been previously thought.

This steep-angled trajectory "was among the worst-case scenarios for the lethality on impact", lead study author Gareth Collins, a professor of planetary science in the Department of Earth Science and Engineering at Imperial College London, said in a statement.

The asteroid leapt over to Earth at a high angle of around 60 levels, taking full advantage of the quantity of gas as well as "hazardous debris" released right into the top environment at the minute of crash- "the very thing that led to a nuclear winter", Collins stated. When heated and disturbed by the impact, these rocks would have decomposed, flinging vast amounts of carbon dioxide, sulphur and water vapor into the atmosphere.

The team's 3D simulations at an angle of 60 degrees reproduced these observations nearly exactly. This eventually contributed to the mass extinction event that killed 75 per cent of life on Earth. Drill samples from recent studies showed evidence of the extreme impact forces and the shape and subsurface of the crater informed the possible impact angle and direction.

The authors said that they regarded 60 degrees as the most likely angle because of the relationship between three points in the crater - its centre, a ring of mountain made of heavily fractured rock inside the crater rim and the centre of dense, uplifted mantle rocks some 30 kilometres beneath the crater.

"Comparison of 3D numerical simulations of Chicxulub-scale impacts with geophysical observations suggests that the Chicxulub crater was formed by a steeply-inclined (45-60° to horizontal) impact from the northeast; several lines of evidence rule out a low angle ( 30°) impact", the study reads.

The researchers say that while the study has also given them important insights into the dinosaur-dooming impact and project how large craters on other planets such as Mars are formed.

The researchers estimated when exactly did the dinosaurs die out and found that some species were already extinct millions of years prior to the impact, and a few others died out a few million years after the asteroid collided with Earth.



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