Type-specimen of NWA 10769 meteorite seen at the polarizing optical microscope
Why is it important to study meteorites?
Meteorites mostly have an age comparable to that of the Solar System, 4.5 billion years, and they are the only objects in our system that we can see and touch directly. Their investigation is therefore very important because it allows us to understand what were the mechanisms that formed them.
In the last 15 years the Mineralogy and Lithology Section of the Museum of Natural History has been conducting research on meteorites. Inspired by the presence, within the Museum collections, of a series of specimens of exceptional historical and scientific interest such as the meteorites Renazzo, Siena and Krasnoyarsk, studies have been undertaken on the textural and compositional characteristics of these samples. We have therefore developed a specific scientific competence that has made the Museum a center of excellence at national level for the study of these materials.
The collaboration with other scientists worldwide has allowed to produce a reference text such as the monograph titled Atlas of Meteorites published by Cambridge University Press. Moreover, the Museum is one of the few structures in Italy officially recognized by the Meteoritical Society, the international certifying body for new meteorites, as a place of deposit of the type specimens of the new meteorites that have been found.
The Monte Milone meteorite
Currently more than 100 type specimens of new meteorites are deposited at the Mineralogy and Lithology section. These are specimens donated by collectors or sellers for the purposes of certification and naming of the meteorite, an activity carried out by the Meteocert Laboratory.
The fields of study
The meteorite research carried out at the Museum has focused on the study of certain meteorite groups, in particular the primitive achondrites called acapulcoites, and of anomalous specimens which are still not part of any known group. Furthermore, studies on the materials generated by the impact of large asteroids on Earth (impactites and tectites) have led to new information on the Libyan Desert Glass.
During the studies on acapulcoites, a new mineral was found, the melliniite, a nickel and iron phosphide, which could have played a fundamental role in the formation of the Earth's core. Research on acapulcoites has produced numerous publications in international scientific journals (see FLORE, the institutional repository of the University of Florence).
The research on anomalous meteorites is particularly interesting: the Acfer 370 meteorite, an ungrouped chondrite, could in fact represent the progenitor of a new group of chondrites rich in magnesium olivine.
Contact: Vanni Moggi Cecchi