Scientists have traced the journey of the dust cloud through the newborn solar system: 4.5 billion years have passed since its formation.
A research team led by the University of Arizona has reconstructed in previously unavailable details the history of the cosmic dust cloud that formed during the birth of the solar system: it happened more than 4.5 billion years ago.
The results obtained give an idea of the fundamental processes underlying the formation of planetary systems, many of which still remain a mystery to scientists.
In the new study, the team developed a new type of structure that combines quantum mechanics and thermodynamics to simulate the conditions that the cloud was subjected to during its formation. The cloud was rich in calcium and aluminum in composition: a similar composition was found in a sample of the Allende meteorite, which fell over the Mexican state of Chihuahua in 1969.
During the work, the authors analyzed the composition of the meteorite, which was presumably formed due to a dust cloud. It was found that the meteorite is mainly composed of the minerals spinel and perovskite, which are also found in rocks on Earth. Similar solids are also found in other types of meteorites known as carbonaceous chondrites, which are of particular interest to planetary scientists because they are remnants of the formation of the solar system and contain organic molecules that may have served as the basis for the formation and development of life.
An accurate analysis of the arrangement of atoms in the meteorite allowed the team to study in detail the structure of the crystal structures. To the team’s surprise, some of the results contradicted current theories about the physical processes that are active inside protoplanetary disks.
As a result, the analysis showed that the dust cloud likely traveled in many orbits around the Sun. It arose not far from the place where the Earth was supposed to form, then flew away towards the Sun and then was thrown into the cold regions of the Solar System. The dust cloud eventually became part of the asteroid, which later disintegrated into pieces. Some of these fragments were due to the gravity of the Earth and fell on our planet in the form of meteorites.