Earth may have had a ring system 466 million years ago

September 16 () –

Earth may have had a ring system that formed about 466 million years ago at the start of a period of meteorite bombardment known as the Ordovician impact peak.

This surprising hypothesis, published in Earth and Planetary Science Lettersis derived from plate tectonic reconstructions for the Ordovician period that pinpoint the locations of 21 asteroid impact craters. All these craters are located within 30 degrees of the equator, despite the fact that more than 70% of the Earth’s continental crust lies outside this region, an anomaly that conventional theories cannot explain.

The research team believes that this localized impact pattern occurred after A large asteroid had a close encounter with EarthAs the asteroid passed inside Earth’s Roche limit, it broke apart due to tidal forces, forming a ring of debris around the planet, similar to the rings seen around Saturn and other gas giants today.

“Over millions of years, material from this ring gradually fell to Earth, creating the peak of meteorite impacts observed in the geological record,” he said. in a statement “We also see that sedimentary rock layers from this period contain extraordinary amounts of meteorite remains,” said lead author Professor Andy Tomkins from Monash University’s School of Earth, Atmosphere and Environment.

“What makes this finding even more intriguing are the “Possible climatic implications of such a ring system,” said.

Researchers speculate that the ring may have cast a shadow on Earth, blocking sunlight and contributing to a major global cooling event known as Andean-Saharan glaciation.

This period, which occurred near the end of the Ordovician, is recognized as one of the coldest in the last 500 million years of Earth’s history.

“The idea that a ring system could have influenced global temperatures adds a new layer of complexity to our understanding of how extraterrestrial events may have shaped Earth’s climate,” Professor Tomkins said.

Typically, asteroids hit Earth in random locations, which is why we see impact craters evenly distributed over the Moon and Mars, for example. To investigate whether the distribution of Ordovician impact craters is not random and is closer to the equator, The researchers calculated the area of ​​continental surface capable of preserving craters from that era.

They focused on stable, undisturbed cratons with rocks older than the middle Ordovician, excluding areas buried under sediment or ice, eroded regions, and those affected by tectonic activity. Using a GIS (Geographic Information System) approach, They identified geologically suitable regions on different continents.

Regions such as Western Australia, Africa, the North American Craton, and small parts of Europe were considered suitable for preserving such craters. Only 30% of the suitable land surface was determined to be near the equator, yet all impact craters from this period were found in this region.

The odds of this happening are How to flip a three-sided coin (if such a thing existed) and get tails 21 times.

The implications of this discovery extend beyond geology, prompting scientists to reconsider the broader impact of celestial events on Earth’s evolutionary history. It also raises new questions about the possibility of other planetary systems Ancient rings may have influenced the development of life on Earth.

Could similar rings have existed at other points in our planet’s history, affecting everything from climate to the distribution of life? This research opens a new frontier in the study of Earth’s past, providing new insights into the dynamic interactions between our planet and the cosmos at large.