A group of astrophysicists has found that the very first stars formed in the Universe 100–200 million years after the Big Bang could have contributed to the formation of water and other chemical elements that are the basis of life.

Population III stars, which are the oldest in the universe, were composed exclusively of hydrogen and helium, elements formed after the Big Bang. The scientists' simulations showed that the explosions of these stars as supernovae, particularly pair-instability supernovae, significantly enriched the surrounding environment with oxygen. This allowed water molecules to form in molecular clouds. In these clouds, the researchers say, the concentration of water could be 10–30 times higher than in modern molecular clouds in the Milky Way.
Water, made up of hydrogen and oxygen, is one of the most common molecules in the universe. Hydrogen, the very first element, was created after the Big Bang, while oxygen came into being through fusion reactions in the cores of stars. As these early stars died, they released oxygen and other important elements into space, which later formed water molecules, carbon, nitrogen, and the building blocks of life.

The simulations also showed that these early stars formed molecular clouds with high concentrations of water and other elements. As early as a few hundred million years after the Big Bang, conditions in such clouds could have been suitable for the formation of life. This discovery challenges the traditional view that water and other life-sustaining elements appeared much later in the history of the universe.
Thus, the first Population III stars not only provided the source of “metals” (elements heavier than helium), but also provided the basis for chemical conditions that could have supported the emergence of life in the early Universe. These results confirm the importance of studying the early stages of the evolution of the Universe for understanding the origin of life.