The reputation of meteorites is generally not good. These rocks contain valuable information that is hard to see with the naked eye, despite their role in the extinctions of dinosaurs. Stardust, one of its compounds, has been studied by an international team of scientists. The University of Cadiz participated in this investigation to help shed more light on the Universe's history.
The chemical composition of the nine presolar grains, or specks of starst, found in two meteorites has been determined. The Isheyevo meteorite is located in Russia and the NWA801, which comes from Morocco, are on the one side. "Presolar grains are one of our oldest solid materials, even before the formation of The Solar System 4.5 billion year ago," says Luc Lajaunie (a researcher at University of Cadiz, and co-author of this study). They are a fossil of space activity more than 4,500,000,000 years ago. Some of the presolar grain have remained the same since their formation.
It was difficult to find these materials in their original form. This is because meteorites can be damaged by impacts with other celestial bodies, heat from the atmosphere, collisions with other planets, and environmental conditions that they are exposed to until they are located and taken to the laboratory.
Researchers from the University of Cadiz assumed control after identifying and isolating presolar grains of both meteorites. Their size is comparable to that of viruses (100 nanometers). This was possible due to the collaboration of Academia Sinica in Taiwan, the Planetary Sciences Division of Research Laboratory of Physics (India), and the Universities of Curtin (Australia), and Copenhagen (Denmark). He focused his work on the analysis of the chemical composition and the physical structure of the pressor grain through an unique microscope located in Spain's Electron Microscopy Division.
They discovered that stardust is composed of silicates. This mineral composition is similar to terrestrial quartz and is the result of supernovae dying off and red giants dying. These stars become dimmed and give rise to solar winds and explosions, which enrich the space with stardust. These particles eventually agglomerate into new celestial bodies and create the elements of our Solar System (planets and satellites ...)).
Lajaunie said that they discovered: "Working in silicates allows for us to better understand the cosmic events of star death and what they produce." These cosmic events are responsible for the creation of fluorine, as well as other elements. Moreover, even though the presolar grains are made from the same types of stars, their chemical compositions remain very similar. Lajaunie says that the most remarkable thing about meteorites and other materials found on Earth is their ability to provide information about how it was formed. The study was published in The Astronomical Journal, a scientific journal.
