According to multiple media reports, a Swedish limestone quarry located west of Stockholm has been the focus of intense scientific scrutiny after the discovery of a meteorite fragment at its site.
It is said that meteorite finds are far from uncommon at the Thorsberg quarry; more than 100 specimens of a meteorite class known as “L chrondites” have reportedly been uncovered at the site over the past two decades. However, this new rock is not of the same class and in fact appears to differ from any other type of meteorite found to date.
Long-lost second asteroid
What the approximately 470 million-year old meteorite does have in common with the L chrondites is that it apparently dates back to the same period – the Ordovician period, which appeared to experience a surge in evolution with the sudden emergence of a large number of new species.
It was believed that this burst of life was due to the collision of two asteroids. A report by New Scientist based on a study published in the Earth and Planetary Science Letters journal explained: “The larger object spawned the cloud of L chondrites that bombarded Earth for about 10 million years. According to one popular idea, this intense meteor shower caused just enough destruction to open up ecological niches and drive life to diversify into a richer assortment. But the fate and identity of the smaller asteroid has long been a mystery.” {{image2-A:R-w:220}}
That mystery may now have been solved; a report from Live Science based on the same study stated that the fact that the L chrondites and the new meteorite shared the same “exposure age” – the length of time spent travelling through space – indicated that they were involved in the same collision. This suggests the recently discovered meteorite could be the second player in the birth of numerous new species on Earth millions of years ago.
Meteorite expert Tim Swindle told Live Science that the meteorite was not necessarily a new find as implied by the authors of the study. He pointed out that a definitive conclusion would be difficult due to the original meteorite’s level of deterioration.
“I think it’s entirely plausible, and it’s a great study, but that’s not a guarantee they’ve got it right,” he said. “But if they didn’t, it’s because of new things we’ll find out in future work, not because of their analysis.”
The scientists involved in the study are reportedly seeking more fragments of this new type of meteorite in other quarries.
The original study is available on www.sciencedirect.com
Source: Earth and Planetary Science Letters, New Scientist, Live Science, Gizmodo