Researchers from Monash University in Australia hypothesize that Earth may have absorbed a passing asteroid, causing it to break into many pieces, forming Saturn-like rings that persisted for tens of millions of years – potentially significantly impacting the planet's climate.
This might look like Earth with rings. Photo: Oliver Hull
According to Andy Tomkins and colleagues at Monash University, they have identified the locations of 21 craters around the world , created by meteorite impacts during the Ordovician period 466 million years ago.
The research team said these impact crater sites are the result of larger objects in a previous belt being pulled out of orbit and crashing into Earth.
Based on the continental movements caused by plate tectonics, the research team said that at that time, they were all located near the equator. They said this is consistent with the belts because they typically form above the equator of planets.
The research team identified a consistency of meteorites in several limestone deposits, and these deposits are also located near the equator.
Tomkins said the research team calculated that the odds of all these craters being near the equator are just 1 in 25 million.
The ring theory could also explain several other mysteries about that period. Meteorite fragments in the craters show signs of not having traveled much through space before crashing to Earth, consistent with material from a relatively close breakup of a large asteroid that created the rings.
Approximately 20 million years later, Earth entered the Hirnantia Ice Age, when temperatures dropped to their lowest levels in half a billion years. Due to Earth's tilt of its axis relative to the Sun, the rings around the equator cast partial shadows on the planet's surface, potentially triggering a global cooling event.
Ha Trang (according to NewScientist)
Source: https://www.congluan.vn/trai-dat-co-the-tung-co-vanh-dai-post312871.html
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