According to research from the University of Cologne in Germany, the cause of the last mass extinction may have been a carbonaceous chondrite, a type of meteorite as old as the solar system.
Sixty-six million years ago, an event changed the natural course of life in the world. Land .
a huge one asteroid struck off the coast of Mexico, particularly in what is now the Yucatan Peninsula .
The force of the space rock was such that it caused the extinction of 75% of animal species, ending the reign of the dinosaurs.
For decades, the origin of this cosmic rock, known as Chicxulub Impactor was a complete mystery to science. It was suspected that it might have come from space, but there was no evidence to prove it.
But now, a new study by researchers from the University of Cologne from Germany changes this panorama. The results, published on August 15 in the academic journal Science They emphasize that The object formed beyond Jupiter’s orbit, more than 800 million kilometers away.
The research also provides new answers to the debate over the nature of the asteroid.
What is the origin of the asteroid that killed the dinosaurs?
Over the past 540 million years, Earth has experienced several mass extinctions. The most recent was the one that occurred 66 million years ago, between the Cretaceous and Paleogene periods, also known as the boundary K-Pg .
According to the JAR The asteroid is estimated to have traveled at a speed of over 25 kilometres per second and its energy was equivalent to 10,000 times the world’s nuclear arsenal. After hitting the Yucatan Peninsula, it vaporized, melted and completely destroyed the ocean water, in addition to vaporizing the rock itself.
A large cloud of dust and gas particles floated in the air and blocked out sunlight, triggering a global winter and stopping photosynthesis. Eventually, many animal species died.
The theory was first put forward in the 1980s by a team led by scientists. Luis Alvarez and Walter Alvarez who were also father and son.
Although the hypothesis initially sparked controversy as it was considered catastrophic, in the 1990s other researchers managed to find the location of the asteroid impact: A huge crater 200 kilometers wide was buried near the Mexican town of Chicxulub.
“We wanted to identify the origin of this shocking object,” he explained. Mario Fischer-Gödde geochemist at the University of Cologne and lead author of the study.
But how did they manage to study this if the asteroid crashed millions of years ago?
In fact, there are still traces of rock scattered all over the planet. This is the little one clay layer which was born after its crash on the surface of the Earth.
Fischer-Gödde and his team therefore set out to analyse the chemical composition of the clay layer in order to obtain new information about the asteroid.
The researchers obtained five samples taken at the K-pg boundary, which is when the impact should have occurred. They compared them to other sediment samples that are nearly 600 million years old and to samples of carbonaceous meteorites.
The analysis focused specifically on Ruthenium isotopes of these samples. And, as Fischer-Gödde explained to Live Science This metal is the “genetic fingerprint” of the rocks of the main asteroid belt, where the Chicxulub impactor originated before crashing into the Mexican coast.
In their study, the team managed to discover that in all five samples of the K-pg limit, they presented the same composition of ruthenium isotopes and that in addition it corresponded mainly to the ruthenium usually found in carbonaceous chondrites (type C).
It is a type of meteorite that formed 4.6 billion years ago, when the solar system was forming, according to Science magazine.
They are distinguished by their high concentration of carbon – hence their name -, water and other molecules called volatiles, which can evaporate easily. Although in the early years of the Earth it was quite common for these objects to collide with it, today they represent less than 5% of the meteorites that fall on the planet.
Following these findings, Fischer-Gödde and his colleagues suggested that it was The cause of the last mass extinction was probably a carbonaceous chondrite.
“All meteorites that fall to Earth, which are fragments of C- and S-type asteroids, come from the asteroid belt. Therefore, it seems very likely that the Late Cretaceous impactor also came from the asteroid belt,” said the lead author.
The team also questioned the theory that what hit Earth was a comet. celestial body composed of rocks, dust and ice particles that orbits the Sun. The composition of ruthenium in the samples analyzed is completely different from that of meteorites thought to be fragments of comets, indicating that it is “unlikely” that the object was a comet, Fischer-Gödde said.
The researchers also suggested that it is possible that the C-type asteroid was pushed toward Earth as a result of collisions with other space rocks, or also under the influence of the outer solar system.
Beyond the results, Fischer-Gödde believes that in the future it will be necessary to continue studying the nature of the asteroids that have hit our planet since its creation, as this could help to elucidate the origin of water on Earth. In addition to this, the researcher from the University of Cologne believes that the analysis of these space objects will allow humanity to prepare for future events.
“If we find that previous mass extinction events could also be linked to C-type asteroid impacts, then… if there is ever going to be a C-type asteroid in an Earth-crossing orbit, we need to be very careful. It could be the last one we witness.” explained the researcher.
Source: Latercera
I am David Jack and I have been working in the news industry for over 10 years. As an experienced journalist, I specialize in covering sports news with a focus on golf. My articles have been published by some of the most respected publications in the world including The New York Times and Sports Illustrated.
