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In July of last year an academic investigation shook materials physics with an unexpected protagonist: a space rock collected in Germany three centuries ago. Inside it housed a mineral whose thermal behavior does not fit into any known classification. The most disconcerting thing is not the material itself (that too), but that it had been gathering dust in a glass case since 1724: no one had looked at it with the appropriate instruments until now. The meteorite of 1724. Called the “Steinbach meteorite” after the German region of Saxony where it fell. The remains quickly joined museum collections due to their exotic origin and beauty, without attracting special attention from the scientific community. Among them, in the National Museum of Natural History in Paris, where the fragment that was used for this research is located. What that fragment contains is meteoric tridymitea form of silicon dioxide extraordinarily rare on Earth. It is a polymorphism of quartz that is only generated under extreme conditions of temperature and pressure, conditions that do not occur in ordinary terrestrial geology, but do occur in meteorite impacts or volcanic environments. Why it is important. In a phrase: because of its properties. The tridymite from the Steinbach meteorite maintains a practically constant thermal conductivity between −193 °C and 107 °C (80 and 380 kelvin), something that beyond meaning that it conducts heat the same whether you are in the cold winter of Iceland or in a heat wave in the desert, it has a peculiarity: no known material behaves like this. This thermal stability is a rarity in itself in materials technology and gives it clear applicability for thermal management: it allows designing electronic devices that do not overheat and aerospace insulation systems with an efficiency unthinkable under the laws of classical physics. Context. In 2009 the physicist Michele Simoncelli together with Nicola Marzari and Francesco Mauri developed a unified equation based on the Wigner transport formalism capable of simultaneously describing the thermal behavior of crystals, glasses and any intermediate state. That equation theoretically predicted the existence of materials with temperature-invariant thermal conductivity like this one. The problem is that no one had found that material in the real world. In the universe, most minerals form under Earth’s pressures and temperatures that force atoms to adopt standard crystal lattices. But in the asteroid belt, the remains of distinct protoplanets undergo cooling processes and catastrophic collisions that generate mineral phases that do not exist naturally in the Earth’s crust. Tridymite is common in volcanic rocks, but this one of meteoric origin has the advantage of having been thermally stabilized in space for millions of years. Something doesn’t add up. Until now, science assumed that a solid material must be either a crystal (ordered structure) or a glass (ordered structures) and its thermal properties depended on that structure: the thermal conductivity of a crystal decreases with increasing temperature because the vibrations of the crystalline lattice (the phonons) disperse among themselves with more intensity. Just the opposite happens in glass because its internal disorder facilitates additional ways of transmitting heat when heated. They are opposite trends, robust and well documented experimentally for decades. The Steinbach meteorite breaks the rules and behaves like both at the same time. Steinbach meteoric tridymite has an atomic structure that presents order in the chemical bonds like a crystal and geometric disorder in the arrangement of those bonds like a glass. This combination generates an exact compensation between both transport mechanisms, the propagation mechanism (typical of crystals) and the tunneling mechanism (typical of glass), which is what the research team calls PTI conductivity, propagation-tunneling-invariant. How they discovered it. The discovery it has been possible thanks to thermoreflectometry, which measures variations in the optical reflectivity of a surface when it is thermally excited with a pulsed laser, allowing thermal conductivity to be inferred with high resolution. What they saw was that the silicon atoms were not in perfect rows, but they were not random either: they followed a “middle-range order” sequence that previously only existed in mathematical models, confirming point by point the predictions of the Wigner equation. Yes, but. The Meteoric tridymite is disruptive in materials technology, the problem is reproducibility and scarcity. So far we have only found this material in the Steinbach meteorite, a limited sample of an astronomical milestone that occurred three centuries ago. Obtaining it from meteorites is simply not feasible and the challenge of manufacturing this glass-crystal synthetically is not exactly small. A curiosity: the paper explains that in the Gale crater Martian tridymite has also been detected, raising questions about how it has influenced the geological history of the red planet or opening the possibility of eventual space mining. On the other hand, and although it is true that the material defies the laws of physics, it is important to highlight that we are talking about current physics: it is not that the laws were false, it is that they were simply incomplete. In Xataka | In 2023 an asteroid disintegrated off the coast of Normandy. At that time we were not aware of how lucky we were In Xataka | In 2011, a collector bought a meteorite in Morocco. It has turned out to be direct evidence of thermal water on Mars Cover | Fred Kruijen and Batu Gezer