Billions of years ago, Earth was frequently struck by asteroids of various sizes. Scientists believe that one such asteroid, which was 200 times larger than the rock that wiped out the dinosaurs, came from space and crashed into Earth approximately 3.26 billion years ago. Although there was less oxygen on our planet at that time, there was still liquid water and the first simple living organisms existed. Despite the fact that the asteroid's impact should have obliterated life, scientists think this event actually led to its flourishing. The study was published in the journal Proceedings of the National Academy of Sciences, as reported by IFLScience.
The authors of the study analyzed rock samples in South Africa and found evidence of an asteroid impact on Earth over 3 billion years ago from an asteroid named S2. Researchers believe this asteroid was four times larger than Mount Everest (the highest mountain on Earth, which stands at just over 8.8 km) and approximately 200 times larger than the asteroid that killed the dinosaurs and most of life on Earth over 60 million years ago. The research demonstrated how this colossal impact could have influenced the earliest life forms on our planet that existed 3.26 billion years ago.
Scientists posit that the asteroid's impact triggered a massive tsunami that altered the composition of the ancient ocean and led to the ejection of rocks into coastal areas. Additionally, the impact caused the atmosphere to heat up, evaporating the upper layer of the ocean and filling Earth's atmosphere with a vast cloud of dust. The lack of sunlight halted photosynthesis.
Although the devastation was immense, the simple life that inhabited the planet at that time, as research indicates, managed to survive the catastrophe. Scientists discovered that microorganisms quickly recovered, leading to a sharp increase in the population of single-celled organisms that feed on phosphorus and iron.
Researchers believe that iron was lifted from the depths of the ocean during the impact and transported to coastal regions by the tsunami. As for phosphorus, it was brought by the asteroid itself, and its quantity increased due to erosion on land. Thus, some microorganisms, albeit for a short time, thrived after the impact event.
According to the study's authors, while most asteroid impacts did not bring any benefits to life on Earth in the distant past, new rock analysis shows that sometimes the opposite was true, and early life could flourish in seemingly adverse conditions.
Scientists have found evidence of seven more asteroid impacts in the early epochs of Earth's existence and now intend to continue their research to better understand how these impacts affected not only life on Earth but the entire planet as well.