Despite covering nearly 70% of Earth's surface, the origins of water have long remained a cosmic mystery. Now, groundbreaking research suggests that water might have formed in the fiery aftermath of the universe’s first supernova explosions—100 to 200 million years after the Big Bang.Scientists from the University of Portsmouth have unveiled compelling evidence that the essential ingredient for life existed billions of years before planets like Earth even began to take shape. Their study, published in Nature Astronomy, uses advanced computer simulations to reveal how the remnants of dying stars became cosmic cradles for water formation.The research suggests that water molecules first emerged when the universe’s earliest stars—massive celestial bodies that formed about 100 million years after the Big Bang—reached the end of their lives and exploded into supernovae. As these stellar explosions released immense amounts of oxygen into space, the element mixed with the surrounding hydrogen in dense, cooling clouds, leading to the formation of water.“These dense, dusty cores are not only where water first formed in abundance, but they also likely provided the building blocks for the first planets,” explained Dr. Daniel Whalen, one of the study’s authors.Using simulations, the team modeled the aftermath of two supernova explosions—one from a star 13 times the mass of the Sun and another from a star 200 times its mass. Their findings indicate that these cosmic explosions produced significant amounts of oxygen, which in turn contributed to water formation.Also read: Terrifying study predicts exactly how many people will DIE in fires caused by climate change by 2100Water, with its simple H₂O structure, consists of two elements: hydrogen and oxygen. Hydrogen was among the first elements formed in the early universe, alongside helium and lithium, within minutes of the Big Bang. However, oxygen—being a much heavier element—had to be forged inside stars through nuclear fusion.As the first stars aged, they burned through their hydrogen fuel and collapsed in violent supernovae. These stellar explosions, reaching searing temperatures of up to 1,800,000,000°F (1,000,000,000°C), fused hydrogen and helium into heavier elements, including oxygen. This newly formed oxygen was then ejected into space, where it eventually met hydrogen and formed water.Simulations revealed that smaller supernovae could generate the equivalent of one hundred-millionth to one millionth of a solar mass of water within 30 to 90 million years. Meanwhile, larger stellar explosions could produce as much as 0.001 solar masses of water in just 3 million years. If this water survived the chaotic formation of galaxies, it may have contributed to the conditions necessary for life.Perhaps the most astonishing revelation is that these early cosmic events may have shaped the water-rich environments of habitable planets like Earth. The dense ‘molecular cloud cores’ where water formed most abundantly are believed to be the origins of protoplanetary disks—the swirling clouds of gas and dust that eventually coalesce into planets and stars.The researchers note: “These disks would have been heavily enriched by primordial water, to mass fractions that were 10–30 times greater than those in diffuse clouds in the Milky Way… only slightly lower than those in the Solar System today.”Also read: Did life really exist on Mars? Ex-CIA agent claims 'lost civilization' on Red planet & 'evidence' to prove it