First supernovae may have seeded rocky planet building blocks 100 million years after the Big Bang

New research suggests that the building blocks of rocky planets may have started forming as early as 100 million years after the Big Bang, far earlier than previously believed and long before the first galaxies emerged. According to scientists at the University of Portsmouth, these foundational elements were likely created through the explosive deaths of some of the earliest stars in the universe, known as Population III stars. These stars, which were massive and short-lived, exploded in powerful supernovae, scattering essential elements like carbon, oxygen, and iron throughout the cosmos. The study challenges previous assumptions that planet formation began billions of years after the Big Bang. Instead, it indicates that the processes necessary for creating planets might have initiated much sooner. Dr. Daniel Whalen, from the University of Portsmouth’s Institute of Cosmology and Gravitation, explained that his team’s research, led by Ph.D. student Chris Jessop, used advanced simulations to model how these early stellar explosions contributed to the formation of planetary materials. Their findings suggest that the precursors of terrestrial planets could have formed around low-mass, long-lived stars in the aftermath of these initial cosmic events. One key factor in this early planet formation was the occurrence of a specific type of supernova called a pair-instability supernova. These explosions are exceptionally powerful, capable of dispersing more than 100 times the mass of the Sun in heavy elements within a single event. This abundance of heavy elements could significantly enrich surrounding gas clouds, allowing them to collapse under gravity and form protoplanetary disks. Such disks, similar to the ones that gave rise to our solar system, contain the raw materials necessary for planet formation. According to the researchers, their simulations revealed a protoplanetary disk around a young star approximately 70 percent as massive as the Sun. Within this disk, enough solid material accumulated to produce several Earth masses’ worth of planetary building blocks at a distance comparable to Earth’s position in our solar system. Additionally, the disk contained considerable amounts of water, only slightly less than what was present during the formation of our solar system. This implies that planets forming in such environments could have acquired water in a manner similar to Earth, potentially supporting conditions suitable for life. The implications of these findings extend beyond the mere timing of planet formation. They raise questions about whether habitable worlds could have emerged much earlier in the universe’s history. If the conditions for forming planets, and possibly life, existed so soon after the Big Bang, it opens up new possibilities for understanding the origins of life and the distribution of habitable environments across the cosmos. The study, titled “Planet Formation at Cosmic Dawn: Planetesimals in H₂O-Rich Disks Around Low-Mass Stars,” has been accepted for publication in The Astrophysical Journal Letters and is currently available on the arXiv preprint server. It represents a significant step forward in understanding the early stages of cosmic evolution and the processes that lead to the formation of planets and potential habitats for life. The research team includes Eduard I. Vorobyov and other contributors whose work focuses on astrophysics and planetary science. Their findings underscore the dynamic nature of the early universe and highlight the complex interplay between stellar explosions, elemental enrichment, and the eventual emergence of planetary systems. As further studies are conducted, scientists will continue to explore the extent to which these early processes influenced the development of the cosmos as we know it today.