Scientists Found a Quasicrystal From a 1945 Nuclear Explosion
Researchers from the Los Alamos National Laboratory (LANL), which was founded during WWII for the design of nuclear weapons as part of the Manhattan Project, discovered a new quasicrystal created by the first-ever nuclear explosion at Trinity Site, New Mexico, on July 16, 1945. Their findings are published in the journal PNAS.
The authors of the study stated that new discovery frames the quasicrystal's creation by a nuclear weapon in the context of physical processes carried out over hundreds of millions of years in deep space.
The material sample could, therefore, help future generations to better understand the chain of events set in motion by nuclear explosions — this insight, they argue, could "aid in nuclear nonproliferation."
This newly found quasicrystal is now the oldest known human-made quasicrystal, with an unmistakable timestamp: July 16, 1945. https://t.co/GV1fh5X2Ya— Los Alamos Lab (@LosAlamosNatLab) May 17, 2021
"Understanding another countries' nuclear weapons requires that we have a clear understanding of their nuclear testing programs," Terry C. Wallace, director emeritus of Los Alamos National Laboratory and co-author of the paper about the discovery, explained in a press statement.
"We typically analyze radioactive debris and gases to understand how the weapons were built or what materials they contained, but those signatures decay. A quasicrystal that is formed at the site of a nuclear blast can potentially tell us new types of information—and they'll exist forever," Wallace continued.
The oldest known human-made quasicrystal
In their study, the LANL researchers explained that the quasicrystal created by the Trinity explosion has 5-fold rotational symmetry, which is impossible in a natural crystal. The new quasicrystal's indisputable moment of origin — verified by its radioactivity, composition, and discovery location — makes it the oldest known human-made quasicrystal.
Unlike regular crystals, a quasicrystal's atomic structure doesn't follow a periodically repeating pattern.
The specific crystal discovered by the team at LANL was an accidental byproduct of the first atomic bomb test, which caused sand, a test tower, and copper transmission lines to fuse into a material known as trinitite.
For the Trinity bomb test, a nuclear device called "the Gadget" was placed atop a purpose-built steel tower and was detonated while scientists from the Manhattan Project watched from a safe distance. Once detonated the fireball from the explosions resulted in a mushroom cloud measuring 40,000 feet (12.2 km) in diameter.
The discovery means that the trinitite sample was formed on July 16, 1945, at Trinity Site, New Mexico, years before quasicrystals were first discovered by the scientific community in 1980.
Discoveries for future generations await
The natural creation of quasicrystals frames the power of nuclear explosions in a frightening context. In 2016, researchers from the University of Florence discovered a quasicrystal in a sample from the Khatyrka meteorite, which was discovered in Russia and dates back hundreds of millions of years. Before reaching Earth, Khatyrka had a long history of violent collisions leading to shock-melting at over 5GPa of pressure at 1,200C, according to a report by Astronomy.
The researchers behind the new paper on the Trinity quasicrystal wrote that the newly discovered sample currently hides secrets that will be revealed by future generations of scientists with more advanced technologies.
"This quasicrystal is magnificent in its complexity—but nobody can yet tell us why it was formed in this way," Wallace explained.
"But someday, a scientist or engineer is going to figure that out and the scales will be lifted from our eyes and we will have a thermodynamic explanation for its creation," he continued. "Then, I hope, we can use that knowledge to better understand nuclear explosions and ultimately lead to a more complete picture of what a nuclear test represents."