A strange crystal-like mineral was recently found inside of a meteorite that crashed into the Earth nearly 15,000 years ago. The reason it’s strange is how the fragile structure managed to survive both the impact and 15,000 more years on the Earth. Equally mysterious is how a crystal would have formed in space to begin with.
The mineral is being called a quasicrystal because it resembles a crystal but its atoms aren’t arranged as regularly as they are in crystals that form naturally on the Earth. This quasicrystal hitched a ride inside of a meteorite which survived untold eons in space and then an impact on the Earth, making its survival a surprise.
“The difference between crystals and quasicrystals can be visualized by imagining a tiled floor,” a statement by Princeton University in a press release said. “Tiles that are six-sided hexagons can fit neatly against each other to cover the entire floor. But five-sided pentagons or 10-sided decagons laid next to each will result in gaps between tiles.”
This quasicrystal has yet to be formally named and it’s only the second one ever discovered and the first natural decagonal crystal ever found.
When we say decagonal, we mean that you can rotate the sample by one-10th the way around a circle around a certain direction and the atomic arrangement looks the same as before,” lead researcher Paul Steinhardt, a Princeton University physicist, told Live Science in an email. “So, each layer has this 10-fold symmetry and then the layers are stacked with equal spacing.”
Researchers are now trying to work out how quasicrystals could form in a four and a half billion year old meteorite – about the same age as our solar system.
“The formation of this quasicrystal happens to be linked to the formation of one of the first meteorites to have formed in the solar system. It is telling us that exotic minerals could exist back then, well before there was an Earth and well before most types of minerals we know,” Steinhardt wrote. “They would be part of the building blocks of the solar system, including planets and asteroids. Yet, we did not know before now that these quasicrystals were part of that story and we do not understand yet how they formed.”
By understanding how this quasicrystal formed, scientists may gain insight into “novel processes in the early stages of the solar system that influenced the formation of planets, including the Earth,” he said.
The results were published online March 13 in the journal Scientific Reports.
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