Scientists from Lund University in Sweden have tracked the flow of meteorites to Earth over the past 500 million years. To do this, scientists have dissolved nearly ten tons of sedimentary rocks from the ancient seabed. The research results are published by the Proceedings of the National Academy of Sciences.
Several thousand meteorites land on the Earth’s surface every year. Space rocks originate from the asteroid belt between Mars and Jupiter, where celestial bodies frayed by giant collisions revolve around the Sun.
Meteorites contain a small proportion of the mineral, chromium oxide, which is highly resistant to degradation. Microscopic grains of chromium oxide were screened out in the laboratory and serve as a kind of “time capsules”, providing scientists with an abundance of information.
To conduct the study, researchers from the Astrogeobiology Laboratory at Lund University dissolved nearly ten tons of sedimentary rocks from the ancient seabed in strong acids. The fact is that the sediment contains the remnants of meteorites, and their chemical composition can be determined when they fall to Earth.
In total, they extracted chromium oxide from nearly 10,000 different meteorites that have fallen to Earth over the past 500 million years.
The results of the study refuted the existing theories. Thus, the researchers determined that large collisions in the asteroid belt, as a rule, do not greatly affect the number of collisions with the Earth.