2 weeks Ago By Amit Malewar
All large bodies in the solar system have rings. Even Mars is believed to have had a ring in the past, which raises the question of whether Earth also had a ring in the past. A new study from Monash University scientists suggests that Earth may have had a ring system that formed around 466 million years ago, during the middle Ordovician , from ca.
466 Ma. The findings challenge our understanding of Earth’s ancient history . Ordovician Period, in geologic time, is the second period of the Paleozoic Era.
This period was unusually intense meteorite bombardment known as the Ordovician impact spike . Scientists studied the ancient plate tectonics and the positions of 21 asteroid impact craters from the Ordovician period. All these craters are within 30 degrees of the equator, even though most of Earth ‘s land is far from the equator, which traditional theories can’t explain.
According to scientists, this pattern occurs due to a large asteroid’s closer approach to Earth. However, the Earth’s tidal forces broke the asteroid apart, creating a ring of debris around the planet, like the rings around Saturn and other gas giants. Over millions of years, debris from this ring gradually fell to Earth, leading to the increased meteorite impacts seen in the geological record.
Lead study author Professor Andy Tomkins, from Monash University’s School of Earth, Atmosphere and Environment, said, “We also see that layers in sedimentary rocks from this period contain extraordinary amounts of meteorite debris.” The potential climate implications of such a ring system make this study even more enjoyable. Scientists think the ring might have cast a shadow on Earth, blocking sunlight and causing a major global cooling event called the Hirnantian Icehouse.
Professor Tomkins said, “The idea that a ring system could have influenced global temperatures adds a new layer of complexity to our understanding of how extra-terrestrial events may have shaped Earth’s climate.” Asteroids usually hit Earth randomly, so craters are spread evenly on the Moon and Mars. Scientists calculated which continental areas could preserve craters from that time to see if Ordovician impact craters are more concentrated near the equator.
They focused on stable, old cratons and excluded areas covered by sediments, ice, or affected by erosion and tectonics. Using GIS (Geographic Information System), they found that regions like Western Australia, Africa, the North American Craton, and parts of Europe were suitable for preserving craters. Despite only 30% of these suitable areas being near the equator, all Ordovician craters were found there.
This is as unlikely as flipping a three-sided coin and getting the same result 21 times in a row. The implications of this discovery extend beyond geology, prompting scientists to reconsider the broader impact of celestial events on Earth’s evolutionary history. Journal Reference:.
