Scientists have been aware for decades that about 66 million years ago, an enormous rock slammed into our planet, resulting in the worst mass extinction of life forms to ever take place on Earth. According to a report by Science Daily, the impact caused the creation of the Chicxulub crater located in the Yucatán Peninsula in Mexico, which is thought to have exterminated about 75% of species inhabiting our planet at that time, including dinosaurs.However, recently, scientists have managed to reveal the nature of the asteroid, or rather to determine what kind of meteorite it was similar to.Recently published research states that the asteroid, responsible for the Chicxulub crater, belongs to a special kind of meteorites called carbonaceous chondrites and, more precisely, to the Ornans class of them.The scientists made this discovery after analyzing samples from the geological formation that was formed as a result of the Chicxulub impact. The study revealed that there were similarities between the composition of the impact material and carbonaceous chondrite meteorites existing on the planet Earth.Unlike other types of meteorites often exhibited in museums, the carbonaceous chondrites, in particular those of the Ornans type, have unique composition. “Carbonaceous chondrites of the Ornans class are definitely not like the typical meteors you find in museum collections,” said Dr. Philippe Claeys, who worked on the study as a visiting professor at the University of British Columbia.According to Dr. Claeys, this kind of meteorites carries fewer quantities of volatiles compared to other types of meteorites. “CO contains far less of such volatiles as carbon, zinc, water, and sulfur, which means there is little chance this kind of meteorite could cause global warming,” says the scientist.This discovery does not affect our knowledge about the causes of extinction. However, it does disprove several previous assumptions about the effect of sulfur emission at the time of impact. “This discovery does not affect our hypothesis concerning the causes of extinction; however, it makes us less sure that sulfur from the impactor was the ‘smoking gun.’ Fine debris that entered the atmosphere was more likely the main problem,” Claeys continued.The massive quantity of dust and debris was generated by the impact of the asteroid on Earth, which led to the blocking of sunlight, temperature changes across the planet, and the cessation of plant growth, thus causing the breakdown of food chains. It is considered that such an environmental disaster greatly contributed to the extinction of dinosaurs and other life forms.This finding allows for better understanding the course of the journey of the asteroid in space. Based on the obtained evidence, it can be assumed that the Chicxulub impactor formed in the outer part of the asteroid belt between Mars and Jupiter.Although asteroids of this size collide with the Earth very seldom, the study of similar cases as the Chicxulub one will enable scientists to better comprehend not only the history of our planet but also threats that near-Earth objects may pose in the future. Notably, this collision marked the end of dinosaurs and opened the way for mammals, including people.
