Incredible GIF Shows Early Earth Being Pummeled By Asteroids
Scientists have known that, just like the other planets, Earth must of taken a few cosmic punches, but until now, they had yet to quantify just how many.
A new study, published July 30 in Nature, attempts to reconstruct the history of Earth's first half billion years and it ain't pretty.
Since Earth's rock record earlier than about 4 billion years ago has been damaged through natural forces like plate tectonics, researchers constructed their model by looking at the impact data from the moon and local planets, as well as the size distribution of our current asteroid belt.
They conclude that the bombardment was so intense during this period that, "no substantial large region of Earth's surface could have survived untouched," wrote the researchers.
Based on their models Earth could have been hit by up to four cosmic projectiles larger than 600 miles in diameter, just under the width of Texas. Three to seven more were likely about half that size, but still capable of "global ocean vaporization," according to the researchers. That's not to mention all the smaller ones.
You can watch a simulation of the affected areas below. While the smaller projectiles (roughly six miles wide), would have left a crater about 60 miles wide, projectiles larger than about 60 miles wide would have also melted the surrounding area, creating an even bigger mess, Marchi said.
The GIF below shows the impacts the model suggests happened. They go forward in time from red to blue (4.5 billion years ago to 3.5 billion years ago).