Australian scientists have found traces of a giant asteroid that fell to Earth in the most ancient period of its history. In terms of destructiveness, his fall is one of the first places. The discovery is reported in the journal Precambrian Research.
In northwestern Australia, geophysicists have discovered spherules (small balls) formed when an asteroid hits the ground. The same spherules were found in bottom sediments aged 3.46 billion years.
According to scientists, the asteroid should have been 20 to 30 kilometers in diameter and leave a crater several hundred kilometers wide. “Humanity has never seen such a blow. It sent giant tsunamis across the ocean, rock shifting and magma outflow,”said study author Andrew Glikson.
At the same time, the exact place of the asteroid impact remains unknown. All craters of that era have long been "erased" by volcanic and tectonic activity. Scientists were able to learn about the impact thanks to the discovery of spherules in a layer of bottom sediments between two volcanic layers, which made it possible to carry out accurate dating.
In that era (3.8-3.9 billion years ago), dozens of asteroids fell to the surface of the Moon - it was because of them that numerous craters arose. Scientists hope to find traces of similar impacts on Earth - there were hundreds of them, according to geophysicists.
