The asteroid that killed the dinosaurs hit Earth at the worst possible angle

66 million years ago quite large pebble hit Earth. The result of this event, or rather collision, was the removal of dinosaurs from the Earth’s surface. Recent research indicates that the asteroid has met Earth at the worst possible angle.

Collision with such a huge object, moving at enormous speed in any case would lead to disaster, but in this case the object entered the Earth’s atmosphere at a very large angle, making its impact more destructive than if the angle were smaller.

As part of the latest research, scientists have created models of the meteoroid flight trajectory toward the Earth and 3D simulation to track the collision from beginning to end: from approaching Earth, to collision and to create a giant crater. The asteroid flew to the place of collision from the north-east and hit the Earth at an angle of 60 degrees, thus maximizing the amount of gas released into the atmosphere, which over time turned out to be a catastrophic event for the climate.

What and how hit the Earth?

In this way, 66 million years ago, the Mesozoic ended with a powerful explosion. The asteroid impact caused global climate change and led to mass extinction, which removed 75 percent of the Earth. life, including all non-volatile dinosaurs.
The trail of the collision, which is visible until today, is the powerful Chicxulub impact crater with a diameter of 200 km located under the Yucatan Peninsula.

As part of their simulation, scientists assumed that a 17 km diameter planetoid at 43 000 km / h hit Earth.

To visualize the direction and angle at which the asteroid hit, scientists analyzed the asymmetrical structures in the crater at a depth of up to 30 km below the surface. Although earlier research involved creating models of crater formation at impact, it was only now that researchers first used data on subsurface structures to create a crater model during later stages of impact, when the crater was finally taking shape.

Simulations indicate that if we take an object about the size and mass of this asteroid 66 million years ago and direct it towards the Earth at a speed of tens of thousands of kilometers per hour, it will knock out a crater very reminiscent of Chicxulub.

According to the researchers, hitting the planetoid at such an angle caused the maximum possible loss. Simulations indicate that hitting Earth from every other angle, the planetoid would knock out into the atmosphere up to three times less sulfur and carbon dioxide.

Professor Gareth Collins of Imperial College London admits that such a flight trajectory was the worst possible scenario for living on Earth at that time. Such a collision placed much more debris in the upper atmosphere, which in turn led to nuclear winter.

The results of the study were published on May 26 in the journal Nature Communications.

The asteroid impact changed the bottom of the crater

The asteroid impact on the current Yucatan Peninsula has left another unusually clear mark. In another, completely independent article published on May 29 in the journal Science Advances, researchers reported that the collision caused superheated sea water to penetrate the interior of the earth’s crust, where it locally changed the chemical composition of the rocks for over a million years.

Tectonically, the Yucatan Peninsula has been calm for 66 million years. Researchers from Expedition 364 implemented as part of the International Ocean Discovery Program drilled 1335 m below the surface of the crater and obtained long cores of sediments and rocks.

Analysis of the minerals in the cores immediately showed that they underwent hydrothermal changes, ” says planetologist David Kring of the Lunar and Planetary Institute in Houston. The unusually high temperature of the heated sea water caused chemical reactions in the minerals themselves, which changed some minerals into others. By identifying different types of minerals, researchers concluded that the initial liquid temperature was over 300 degrees Celsius, to later drop to around 90.

Chemically changed rocks beneath the crater reach depths of up to four to five kilometers below the surface, and paleomagnetic data indicate that such hydrothermal conditions at the asteroid impact site lasted for over a million years.

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The asteroid that killed the dinosaurs hit Earth at the worst possible angle

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