A meteorite that may have been up to 200 times bigger than the one that killed the dinosaurs might have triggered the formation of complex life on Earth. The S2 meteorite hit Earth approximately 3.26 billion years ago, bringing a one-two punch of destruction and proliferation. While life was limited prior to the impact, researchers believe that it may have bloomed in the aftermath because of nutrients released.
Rock and roll
The S2 meteorite “likely had significant effects on early life,” said a study published in the journal Proceedings of the National Academy of Sciences. The effects included massive destruction along with stimulation of life on Earth. The meteorite “triggered a massive tsunami that would have churned the ocean floor with debris, flushing into coastal regions,” Space.com said. S2 was between 23 and 36 inches in diameter. “Picture yourself standing off the coast of Cape Cod, in a shelf of shallow water,” said Nadja Drabon, an early Earth geologist and assistant professor in the Department of Earth and Planetary Sciences at Harvard University, who is the lead author of the study. “Then all of a sudden, you have a giant tsunami sweeping by and ripping up the sea floor.”
S2 initiated several life-giving processes. “The impact released essential nutrients, such as phosphorus, on a global scale,” Drabon said to CNN. Heat from the impact boiled off the topmost layer of the ocean while also heating the atmosphere. “Overall, this is very good news for the evolution of early life on Earth, as impacts would have been much more frequent during the early stages of life’s evolution than they are today.” While scientists posit that life did exist prior to this point, “no complex life had formed yet, and only single-celled life was present in the form of bacteria and archaea.”
With the aftermath of S2 came “sharp spikes in populations of unicellular organisms that feed off the elements phosphorus and iron,” which were “likely stirred up from the deep ocean into shallow waters,” said Harvard University. Because of this iron metabolization, bacteria flourished. “This shift toward iron-favoring bacteria, however short-lived, is a key puzzle piece depicting early life on Earth.”
Meteor mayhem
Scientists have long theorized that a meteor may have brought life to Earth. “Early in Earth’s history, space rocks frequently hit the young planet. It is estimated that ‘giant impactors,’ greater than 6.2 miles (10 kilometers) across, pummeled the planet at least every 15 million years,” said CNN. “We have long known that on the young Earth, meteorite impacts were both more frequent and, on average, larger than today,” Andrew Knoll, a Harvard geologist and study co-author, said to NBC News. “While people have speculated about the potential biological and environmental consequences of ancient impacts, there has been little hard data to test varying hypotheses.”
One such theory was that the building blocks for life on Earth may have come from space. An April 2024 study explored whether carbon, carbon monoxide and ammonia, all important for life, “could combine there to create peptides, or small chains of amino acids, essential to life on Earth,” said Astronomy. “If so, these peptides could have been delivered to Earth after its formation to aid in the development of early life,” mainly from asteroids and meteors.
Nutrients from the impact led to a “fertilizer bomb”
