An ‘impossible’ quasi-crystal was created in the world’s first nuclear bomb test

At 5:29 a.m. on July 16, 1945, in the state of New Mexico, a terrible slice of history was written.

The calm of dawn was shattered when the US military detonated a plutonium implosion device known as the Gadget – the world’s first-ever test of a nuclear bomb, known as the test Trinity. This moment would change the war forever.

The release of energy, equivalent to 21 kilotons of TNT, vaporized the 30-metre (98 ft) test tower and miles of copper wires connecting it to the recording equipment. The resulting fireball fused the tower and copper with the asphalt and desert sand below into green glass – a new mineral called trinitite.

Decades later, scientists have discovered a secret hidden in a piece of this trinitite – a rare form of matter known as a quasicrystal, once considered impossible.

“Quasicrystals form in extreme environments that rarely exist on Earth,” geophysicist Terry Wallace of Los Alamos National Laboratory explained last year.

“They require a traumatic event with extreme shock, temperature and pressure. We don’t usually see that except in something as dramatic as a nuclear explosion.”

Most crystals, from humble table salt to the toughest diamonds, obey the same rule: their atoms are arranged in a lattice structure that repeats in three-dimensional space. Quasicrystals break this rule – the pattern in which their atoms are arranged does not repeat.

When the concept first appeared in the scientific world in 1984, this was considered impossible: the crystals were either ordered or disordered, without any intermediary. Then they were found, both created in the laboratory and in nature – deep within meteorites, forged by a thermodynamic shock of events like a hypervelocity impact.

Knowing that extreme conditions are needed to produce quasicrystals, a team of scientists led by geologist Luca Bindi from the University of Florence in Italy decided to take a closer look at trinitite.

But not the green stuff. Although rare, we’ve seen enough quasicrystals to know that they tend to incorporate metals, so the team went in search of a much rarer form of the mineral – red trinitite, given its hue by the vaporized copper wires embedded in it.

Using techniques such as scanning electron microscopy and X-ray diffraction, they analyzed six small samples of red trinitite. Finally, they were hit in one of the samples – a tiny 20-sided grain of silicon, copper, calcium and iron, with fivefold rotational symmetry not possible in conventional crystals – an “unintended consequence” of warmongering .

“This quasicrystal is magnificent in its complexity – but no one can tell us yet why it formed this way,” Wallace explained in 2021 when the team’s research was published.

“But one day some scientist or engineer will figure this out and the scales will be lifted from our eyes and we will have a thermodynamic explanation for its creation. Then hopefully we can use this knowledge to better understand nuclear explosions and lead ultimately to a fuller picture of what a nuclear test is.”

This discovery represents the oldest known anthropogenic quasicrystal and suggests that there may be other natural pathways for the formation of quasicrystals. For example, lightning-forged molten sand fulgurites and material from meteor impact sites could both be a source of quasicrystals in nature.

The research could also help us better understand illicit nuclear testing, with the eventual aim of curbing the proliferation of nuclear weapons, the researchers said. Studying minerals forged at other nuclear test sites could uncover more quasicrystals, whose thermodynamic properties could be a tool for nuclear forensics.

“To understand other countries’ nuclear weapons, we need to have a clear understanding of their nuclear testing programs,” Wallace said.

“We typically analyze radioactive debris and gases to understand how weapons were constructed or what materials they contained, but these signatures decay. A quasicrystal that forms at the site of a nuclear explosion can potentially give us insights. new kinds of information – and they’ll exist forever.”

The research has been published in PNAS.

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