About 470 million years ago, two asteroids smashed into each other in outer space and shattered into multitudinous pieces. Many of those pieces rained down on Earth over the course of a million years as meteorites, and have become well-known by scientists. But the other space rock involved in the cosmic head-on collision has never been known – until now, thanks to the discovery of a meteorite that’s never been seen before on our planet.
Researchers at the University of California Davis (UC Davis) found the meteorite, which they dubbed Ost 65, at a quarry in Sweden, a famous source for fossil meteorites, or those that have been chemically altered over time.
“Measuring just under four-inches wide, it looks like a gray cow patty plopped into a pristine layer of fossil-rich pink limestone,” says a UC Davis report about the discovery. “The Ost 65 rock is called a fossil meteorite because the original rock is almost completely altered except for a few hardy minerals — spinels and chromite.”
Spinel is a glassy mineral similar to rubies and chromite is an iron-containing mineral.
By analyzing the chromium and oxygen isotopes in those two minerals, the researchers were able to conclude that the meteor was “chemically distinct from all known meteorite types,” according to UC Davis.