Discovery of the first trace of a meteorite hitting the Earth

Scientists have discovered stone spheres dating back 3.48 billion years, formed when meteorites crashed into the ground.

Evidence of the oldest meteorite impact

Evidence of the oldest meteorite impact has been found in a group of volcanic and sedimentary rocks in Western Australia. (Photo: Alamy).

Professor Christian Köberl of the University of Vienna, Austria, and his colleagues may have discovered the oldest evidence of a meteorite hitting Earth. The research results were presented at the 2023 Lunar and Planetary Science Conference to be held in Texas, USA, from March 13 to 17.

In the 3.48 billion year old rock from the Dresser Formation, In Western Australia, a team of experts has discovered structures compatible with a collision from space. It’s the stone sphere (spherule) with a structure and chemical composition showing that the extraterrestrial hypothesis may be correct.

Finding evidence of ancient meteorite collisions on Earth is not easy. Plate tectonics and erosion have erased traces of the events that shaped the planet’s early history. The oldest impact crater on record is Yarrabubba, Western Australia, dating back 2.23 billion years.

However, there are areas on Earth containing older rocks. This is why researchers also look for indirect evidence meteorite crash event – for example, a stone sphere. Spheres can form in a variety of ways, including when meteorites strike the ground and cause molten rock to splash, hardening into small blocks.

To determine whether the Dresser Formation spheres formed as a result of a meteorite impact, Köberl and his colleagues used a series of advanced techniques to analyze their structure and chemical composition. “Alien components make up the majority of the structure of these spheres”he said.

These ingredients include large amounts of iridium, several isotopes of osmium, and nickel-chromium spinel. They also have a characteristic dumbbell or teardrop shape with many bubbles inside. These are common characteristics of meteorite rock spheres because of the way they solidify after impact. The newly discovered stone spheres look very similar to the slightly smaller ones that researchers found in Australia and South Africa.

Finding ancient meteorite impacts is important because Help experts reconstruct Earth’s history. Conditions on early Earth depended greatly on the number of meteorites that crashed. The group of experts is trying to study more rock samples containing meteorite spheres to better understand the ancient collision, and thus better understand the early history of the blue planet.

Article source: VnExpress