Known for its extensive ring system, Saturn is one of them four planets of our solar system which have this special feature. Recently, scientists have hypothesized that Earth may have had its own ring around 466 million years ago.

During the Ordovician Perioda time of major change for Earth’s life forms, plate tectonics, and climate, the planet experienced a peak in meteor impacts. Nearly two dozen impact craters known to have appeared during that time were all within 30 degrees of Earth’s equator, signaling the meteorites may have rained down from a rocky ring around the planet, according to a study published in Sept. 12 in the journal Earth and Planetary Science.

“It is statistically unusual to there are 21 craters all relatively close to the equator. It doesn’t make sense for it to happen. They should be randomly distributedsaid lead author Andrew Tomkins, a geologist and professor of Earth and Planetary Sciences at Monash University in Melbourne, Australia.

No, not only does the new hypothesis shed light on the origin of the peak of meteor impacts, but it may also provide an answer to an unexplained event: A global freeze, one of the coldest climate events in Earth’s history, may have been the result of the shadow of ring.

Scientists hope to learn more about the possible ring. It could help answer mysteries of Earth’s history as well as raise new questions about the influence an ancient ring might have had on evolutionary development, Tomkins said.

Earth also wore a ring like Saturn’s

When a smaller body gets close enough to a planet, it reaches what is known as the Roche limit, the distance where the celestial body has enough gravitational pull to break apart the approaching body. The resulting debris then creates rings around the planet, like those around Saturn that may have formed from debris from icy moons, according to NASA.

Scientists previously believed that a large asteroid broke up within the solar system, creating the meteorites that hit Earth during the Ordovician Period. However, such an impact would likely have caused a more random distribution of impacts, such as the random location of craters on the moon, Tomkins said.

The study’s authors hypothesize that a large asteroid, estimated to be about 7.5 miles (12 kilometers) in diameter, reached Earth’s Roche limit, which may have been about 9,800 miles (15,800 kilometers) from the planet based on measurements of older ruins. The asteroid would have been largely battered by other collisions, making the debris loose and easy to pull away from Earth’s force, Tomkins said.

The ring would have formed along the equator, just as the rings of Saturn, Jupiter, Uranus and Neptune formed. It is also found around each of these planets’ equators, he added.

About 200 impact hits from throughout Earth’s history are known, Tomkins said. By looking at how land masses have moved over time, the authors found that the 21 known craters dating to the Ordovician Period were all near the equator. Furthermore, only 30% of the Earth’s surface suitable for sustaining a crater was located near the equator. If the impacts were random and not from a ring, most of the craters should have formed away from the equator, he added.

The authors also point to a February 2022 study that analyzed impact craters on Earth, the moon and Mars and found signs of the Ordovician impact only on Earth, adding further evidence aligned with the ring theory.

“The paper presents a pleasant idea that connects some mysteriessaid astrophysicist Vincent Eke, associate professor at the Institute for Computational Cosmology at Durham University in the United Kingdom, who was not involved in the new study.

The possibility of future rings

Based on the length of the global cooling period and the dating of craters and meteorite material, Earth’s possible ring could last 20 million to 40 million years, Tomkins said. Collisions between other particles would have thrown the space rocks out of the ring.

Previous research found that the ancient Mars it could also be wearing a ring or rings, and scientists predict the planet may one day have more.

“While rings are associated with the outer, giant planets in the solar system right now, in the next 100 million years or so, Mars will acquire a ring system” said Eke. “Fortunately, for the development of life on Earth, these kinds of (events) are rare at this time!»

Since late September, an asteroid named 2024 PT5 has been traveling close to Earth. The space rock is commonly referred to as a “mini-moon” because it is 2.8 million miles (4.5 million kilometers) from the planet. However, even during the asteroid’s closest pass to date on August 8 at about 352,300 miles (567,000 km), it was nowhere near Earth’s Roche limitsaid Carlos de la Fuente Marcos, a researcher at the school of mathematical sciences at Complutense University. Madrid who has studied the mini moon. De la Fuente Marcos was not involved in the new study.

Also, the proposed Earth ring would have to “be the result of the breakup of a much larger body, as the authors report in their paper,” he added in an email, so the asteroid, likely about 37 feet (11 meters) in diameter, would not it could have made a new ring for Earth.

“(This mini-moon) is just an example of the processes happening in our nearby space region that might lead to what we’re talking about,” Tomkins said. However, “this ring-forming event we believe may have occurred only once in the last 500 million years.”