Water, the essential molecule for life as we know it, was present much earlier in the universe’s history than previously thought, according to a new study published in Nature Astronomy. This groundbreaking research suggests that habitable worlds could have formed billions of years earlier than previously estimated.
The study utilizes advanced modeling techniques to simulate the formation of water in the primordial universe. Researchers found that water molecules began forming after the first supernovae, the explosive deaths of stars. These supernovae were crucial for creating heavy elements, including oxygen, a key component of water (H₂O).
“Before the first stars exploded, there was no water in the Universe because there was no oxygen,” explains Daniel Whalen, a cosmologist at the University of Portsmouth and lead author of the study. “Only simple nuclei like hydrogen, helium, lithium, and trace amounts of barium and boron survived the Big Bang.”
“Oxygen, forged in the hearts of these supernovae, combined with hydrogen to form water, setting the stage for the creation of other essential elements needed for life,” Whalen adds.
The research team investigated two types of supernovae: core-collapse supernovae and Population III (Pop III) supernovae. Core-collapse supernovae produce moderate amounts of heavy elements during their explosions. In contrast, Pop III supernovae are known to expel over ten times the mass of our Sun in metals. Both types of supernovae contribute to the formation of water-enriched gas clouds that disperse throughout the cosmos.
“The primary sites of water production in these remnants are dense molecular cloud cores, which in some cases were enriched with primordial water to mass fractions approaching those found in our Solar System today,” the researchers explain in a preprint of the paper on arXiv. “These dense, dusty cores are also likely candidates for protoplanetary disk formation.”
This research indicates that water, a fundamental requirement for life, was present just 100 to 200 million years after the Big Bang. “Besides revealing that a primary ingredient for life was already in place in the Universe so early, our simulations show that water was likely a key constituent of the first galaxies,” the team adds. This discovery suggests the early universe might have been a surprisingly active environment for prebiotic chemistry.
Advanced telescopes capable of detecting incredibly faint light from the distant, early universe will be crucial for further understanding the history of life and the evolution of the cosmos. Observatories like the James Webb Space Telescope are instrumental in this endeavor, enabling astronomers to unravel the universe’s timeline, from the formation of the first galaxies to their chemical composition.
While we haven’t yet discovered life beyond Earth, studies like this one are helping scientists gain a clearer picture of how life’s building blocks came into existence and how early life might have emerged. This research brings us one step closer to answering fundamental questions about life’s origins in the universe.
