Water surrounds us, falling from the sky, rushing down riverbeds, pouring from faucets, and yet many of us have never stopped to ask where it comes from. The answer is a complicated one, stretching way beyond an incoming tide or a cloud heavy with rain and all the way back to the very origins of the universe.
Shortly after the big bang, protons, neutrons and electrons swarmed in 10 billion degree heat. Within minutes, hydrogen and then helium, known as the lighter elements, had taken shape from these atomic building blocks in a process called nucleosynthesis. (Lithium had a cameo as well.) The heavier elements didn’t appear until much later, when the lighter elements underwent fusion inside of stars and during supernovas. Over time, stars sent wave after wave of these heavier elements, including oxygen, out into space where they mixed with the lighter elements.
Of course, the formation of hydrogen and oxygen molecules and the subsequent formation of water are two different things. That’s because even when hydrogen and oxygen molecules mix, they still need a spark of energy to form water. The process is a violent one, and so far nobody has found a way to safely create water on Earth. Read more