The worst scenario for dinosaurs. Conclusions – groups of scientists who are investigating the fall of a giant asteroid on Earth. The fact that, according to one of the hypotheses, became the cause of the mass extinction of animals and plants of the Mesozoic era. After excavations at the bottom of the Gulf of Mexico, where, in fact, there was a trace from those events, an opportunity appeared to restore the stages of the disaster.
In particular, to understand – why the consequences of an asteroid collision with the planet – were so tragic. Geophysicists from 11 countries combined their knowledge on this subject.
The information was uploaded to a supercomputer and the impact model was calculated. Similar works were before, but for the first time it was possible to imagine the fall in full scale.
As the head of the study explained, the main task was to calculate the flight path. Well, among the conclusions, there is a thesis requiring explanation: “the asteroid fell under one of the deadliest angles.” That is, it was such a detail as the angle of collision that provoked the death of all living things.
History, of course, does not tolerate the subjunctive mood. But in general, such a conclusion suggests itself.
Yucatan, a quiet place of Chixulub on the shores of the Gulf of Mexico. It is possible that it was here that evolution made its most steep turn. Under water – a huge crater with a diameter of 180 kilometers. 66 million years he was left by a 12-kilometer meteorite. For a long time, we actually knew nothing about the collision itself.
But now, having modeled the fall of a celestial body using sophisticated computer simulations, experts have unveiled the veil of secrecy. So, the first: the blow came from the northeast. And the second: the angle relative to the surface was from 45 to 60 degrees. From this, scientists conclude: dinosaurs are terribly unlucky.
Earlier, their colleagues calculated which angle of incidence of meteorites for earthly life is most destructive. And it turned out to be those same 45-60 degrees. It turns out that with this value, the maximum amount of greenhouse gases and suspended matter enters the air. If, for example, a meteorite fell on the ground clearly from top to bottom, the impact on the climate would be several times smaller.
And the most non-hazardous were the cars, like Chelyabinsk: entering the atmosphere from small angles. If a meteorite had passed along the same trajectory 66 million years ago, there is a possibility that giant lizards would have remained masters of the planet!
“It would be a very bad day for dinosaurs anyway. But the angle played a role. If it were sharper, for example 10 or 15 degrees, then, quite possibly, the consequences of the impact would be much less catastrophic. The crater would be less and less air would enter the atmosphere, “explained Gareth Collins, professor of planetology at Imperial College London.
The collision of the Earth with an asteroid led to the so-called Cretaceous-Paleogene extinction. Killed a third of all species existing at that time! The main victims, of course, were dinosaurs. It was not the blow itself that ruined them. And the climate changes that followed.
The fall of the asteroid led to the instant release of about 425 gigatons of carbon dioxide into the atmosphere. This is about 12 years of continuous work of all enterprises created by man. A tremendous amount of sulfur compounds also rose into the sky. Due to the greenhouse effect, it has suddenly become colder. For example, in the same Gulf of Mexico, the water temperature dropped from 25 to 7 degrees! He became like the Barents Sea.
“Dinosaurs just couldn’t survive the cooling by even 20 degrees for 30 years. Because they are not warm-blooded. And warm-blooded, by the way, survived. And a new round of evolution began,” explains Natalya Artemyeva, senior researcher at the Institute of Geosphere Dynamics of the Russian Academy of Sciences, Senior Researcher, Institute for Planetary Research (USA).
However, experts specify: colossal greenhouse gas emissions are a consequence of not only the angle of incidence of the meteorite. Dinosaurs were also fatally unlucky with the site of the collision.
“Chiksulub is also a very specific target. It is a sea target, and there was a lot of calcite, it is chalk, roughly speaking. And when it is heated, carbon dioxide is formed. And there were also many so-called evaporites. They contain sulfur, which is also emitted into the atmosphere. And all this happens at tremendous speeds. That is, it flies out of the atmosphere, then returns to the atmosphere and very quickly envelops the entire Earth, “says Natalya Artemyeva, senior researcher at the Institute of Geosphere Dynamics of the Russian Academy of Sciences, senior researcher at the Institute for Planetary Research (USA).
It turns out that a meteorite would fall to any other place and from a different angle, and the development of life on the planet would go on a completely different path! Maybe now we would not walk the dogs, but hand raptors. Or maybe we would not exist at all.
One thing is certain: no evolutionary zigzags are foreseen in the foreseeable future. Frightened by the fate of the dinosaurs, astronomers scanned the sky near the Earth and took control of all celestial bodies larger than a kilometer.
They assure that in the next hundreds of years not one of them will fly up to a dangerous distance.
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