‘Quite a spectacle!’ 3 billion years ago, Earth was pummeled by giant 10km-long asteroids.
ASTEROIDS the size of major towns once blasted the Earth’s surface three billion years ago, causing collisions on a magnitude comparable to the meteor impact that wiped out the dinosaurs – and they happened far more frequently than scientists previously imagined.
Giant asteroids originally strewn across the early Earth’s surface, creating a ferocious environment. However, scientists have now discovered that space impactor bombardments occurred significantly more frequently than originally thought.
We already know that Earth was impacted by multiple huge meteor strikes before humanity arrived.
The Chicxulub asteroid, which struck Earth around 66 million years ago and wiped out the dinosaurs, was the most notable.
The asteroid is estimated to be 150 kilometers big and caused the Chicxulub Crater, which is 10 kilometers wide and located near the Gulf of Mexico.
Similar asteroids are thought to have had a significant influence in shaping the Earth’s surface and atmosphere into what they are now.
However, it has previously been difficult to quantify how many such catastrophes have occurred throughout the history of our planet.
While we can detect craters on the Moon and other planets, atmospheric weathering and plate tectonics make finding evidence of ancient craters on Earth increasingly challenging.
However, it has since been discovered that these massive asteroid occurrences occurred 10 times more frequently than originally assumed.
According to researchers at the Southwest Research Institute, Earth might have been hit by similar-sized asteroids to Chicxulub every 15 million years between 3.5 and 2.5 billion years ago.
They claim that analyzing’spherules’ can uncover evidence of past asteroid strikes.
Spherules are molten particles and vapours trapped as microscopic spherical particles inside rocks.
Spherules would be produced by each hit, which would eventually get lodged in the Earth’s surface.
They went on to say that the bigger the impact, the more spherules would be produced.
“With this method, we discovered that current models of Earth’s early bombardment drastically underestimate the number of known impacts, as documented by spherule layers,” said researcher Dr Simone Marchi.
“The true impact flux in the period between 3.5 and 2.5 billion years ago could have been up to a factor of ten times bigger than previously estimated.
“This suggests that every 15 million years, we were probably hit by a Chicxulub-sized impact during that early time. It was quite a show!
“These powerful events are quite likely to have significantly affected the Earth’s surface and atmospheric evolution.”
It’s been suggested that a big meteor hit the Earth. “Brinkwire News in Condensed Form.”