Asteroid impacts are undoubtedly one of the most dangerous natural disasters possible. However, catastrophic impacts have not been experienced recently. However, this was not the case in the early Earth period. Earth was beating under the intense bombardment of asteroids from outer space. A new study has revealed that these impacts are occurring much more frequently than previously believed, and may therefore delay the creation of conditions that would support life on Earth.
The impacts examined in the study occurred during the Archaean period, between 2.5 billion and 4 billion years ago. During this time, the planet’s environment was very different, and being bombarded by asteroids undoubtedly made the situation worse.
By analyzing the asteroid remnants, the scientists created a model of the effects of these collisions. According to their findings, published in the academic journal Nature Geoscience, major asteroid impacts occur approximately every 15 million years, 10 times more frequently than current models suggest.
When large asteroids hit Earth, they melted and vaporized part of Earth’s crust, creating a massive cloud of debris on the surface. Pieces of crust spread by this cloud rained down on Earth’s surface again as sand and stone. It appears that the more such deposits in an area, the more asteroid impacts there have been.
The Archaean period was the period when life first began to form on Earth, and also when oxygen in the atmosphere was slowly accumulating. Oxygen itself was not present in significant amounts in the atmosphere until the early Proterozoic era, 2.5 billion to 541 million years ago, after anaerobic algae released it during photosynthesis. However, according to these new findings, it is thought that without the asteroid impacts, oxygen could have accumulated on Earth earlier, and in parallel, life could have emerged earlier.
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