An all-Italian group of researchers has made an important discovery in the field of planetary sciences: the team has found a very rare meteorite in Calabria which contains very rare metallic alloys of aluminum and copper and which contains materials with a forbidden symmetry, the so-called ‘quasicrystals’. The results of the analyzes on the strange meteorite, conducted by researchers from the University of Bari in collaboration with the University of Florence and the Italian Space Agency, were published in the scientific journal “Communications Earth & Environment”.
The rare meteorite discovered in Calabria
The discovery immediately proved to be exceptional: it is the third case in the world of extraterrestrial material containing metal alloys of this type and the second discovery of a micrometeorite containing a quasicrystal of natural origin, after the discovery of the Khatyrka meteorite, which occurred in 2011, thanks to a very expensive and adventurous international expedition that reached the borders of the Russian Far East, in Chukotka, where the meteorite that gave it its name was found.
In this case, the discovery is defined as a case of “Citizen Science”: the micrometeorite, having the shape of a small spherule, was found on Mount Gariglione in Calabria by a collector who, noticing a strange and unusual metallic shine, decided to send it to scholars at the University of Bari to investigate the nature of this apparently inexplicable object. The analyzes carried out promptly highlighted an incredible discovery: the spherule was extraterrestrial. Its singular metallic shine, due to the presence of a metallic alloy of copper and aluminium, has been found in extremely rare previous cases. The scholars were impressed to find that they had an element never found in nature in their hands: a new and very rare quasicrystal present in the meteorite. “I am proud of the work that is done on a daily basis by our researchers – commented the rector of the University of Bari, Stefano Bronzini – and even more so when our logo is placed alongside that of other institutions as in this case. Collaboration is important because it broadens the field of knowledge and recognizes UniBa’s important role on issues in which the University has always invested and believed”.
What are “quasicrystals”
Luca Bindi, full professor of Mineralogy and Director of the Department of Earth Sciences of the University of Florence, explained the nature of quasicrystals: “They are materials in which the atoms are arranged as in a mosaic, in regular patterns but which are never repeated in the same way, unlike what happens in ordinary crystals. It was Dan Shechtman, later awarded a Nobel Prize for his discoveries in 2011, who studied their structure in the 1980s, which also makes them valuable for applications in various industrial sectors. Fifteen years ago, it was I who discovered that this material also existed in nature, thanks to the identification of the first quasicrystal in a sample belonging to the Khatyrka meteorite, preserved in the Natural History Museum of the University of Florence”.
The discovery is decidedly exceptional due to the fact that it is the second discovery of a micrometeorite containing quasicrystals, but also due to the fact that the small spherule was discovered in southern Italy thousands of kilometers from the first discovery and was studied by a group of entirely Italian research led by the University of Bari: “The results of this research – underlined Paola Manzari of the Research and Higher Education Coordination Unit (UCR) of the ASI Matera Space Center – show that a still unknown universe exists of mineralogical phases at the nanoscale in materials of extraterrestrial origin, which still manages to surprise us. The discovery of this anomalous alloy in a chondritic matrix together with the presence of quasicrystals, opens up new scenarios on the origins of the original material from which the fragment detached and provides new elements to understand the mechanisms of formation of the Solar System”. The rare meteorite that arrived from space is now kept in the Museum of Earth Sciences of the University of Bari, where a section dedicated specifically to extraterrestrial samples will be set up.