Water was first produced in the first supernova

Water was first produced between 100 and 200 million years after the Big Bang, according to a study published in Nature Astronomy. According to these simulations, water was formed earlier than expected and is likely to be a key component of the early galaxies.

Until now it was believed that water was produced much later because there would not have been enough oxygen before. In fact, hydrogen and light elements such as helium and lithium were produced in the Big Bang, but heavier elements such as oxygen are due to nuclear reactions or supernovae within stars.

Simulations of the supernovae of two first-generation stars have been made and it has been observed that the oxygen released during these first explosions would react with the surrounding hydrogen. Thus, when the remnants of supernovae had cooled sufficiently for a few million years or tens of millions of years, dense gas clusters containing water would have formed between the components. Ginera, the simulations show that water was probably a key component of the early galaxies.