Produced by: Tarun Mishra Designed by: Manoj Kumar
Around 3.26 billion years ago, a massive meteorite struck Earth, and scientists are now uncovering details of its effects. Geological evidence from South Africa’s Barberton Greenstone Belt provides insights into the early planet and its environment.
The meteorite, estimated to be up to 200 times larger than the one that caused the extinction of the dinosaurs, triggered a massive tsunami, mixing ocean waters and transporting debris from land into the coastal zones. The event significantly altered Earth’s geological landscape.
Nadja Drabon, a geologist and professor at Harvard University, leads a team investigating Earth’s ancient environment. Her work explores how meteoritic impacts like the “S2” event influenced the planet during a time when only simple bacteria and archaea existed.
The impact caused the ocean’s surface to boil and generated dust clouds that blocked sunlight, disrupting photosynthesis. Yet, bacteria, resilient to these conditions, managed to survive and even thrive in the aftermath, according to the team’s analysis.
After the impact, iron stirred from the deep ocean and phosphorus delivered by the meteorite contributed to a population increase of unicellular organisms. These elements fueled iron-metabolizing bacteria, creating a temporary yet significant boost in microbial life.
Drabon’s research suggests that while meteorite impacts were catastrophic, they may have also created conditions favourable to life. This challenges the view that all impacts were destructive and highlights their potential role in supporting early ecosystems.
Drabon and her team conduct detailed fieldwork in South Africa, collecting rock samples to study sedimentology, geochemistry, and carbon isotope compositions. These efforts provide a clearer picture of how early Earth evolved under the influence of repeated meteorite impacts.
The Barberton Greenstone Belt contains evidence of at least eight impact events, including the S2. Drabon’s team plans to continue their research, probing deeper into Earth’s history to better understand the relationship between meteorite impacts and the development of early life.