Water is the most important element in the search for traces of life in the Universe. Without water, scientists believe that it is impossible for life to develop. So knowing when the latter appeared in our Universe is a primordial question.
It is very difficult to imagine what Earth could have looked like when it first started as planets. If the image of a lava ball is often mentioned, the latter is today criticized and the construction of the Earth is much more complex. But when scientists take a look at the beginnings of the Universe, things get even tougher. Indeed, if the Big Bang theory is accepted today by the scientific community, it has not ruled out all the gray areas concerning the construction of our universe.
Thus a recent study carried out by an international team of researchers concluded that water could have arrived very early in the history of the Universe. To understand, it is now almost certain that the Universe is 13.7 or 13.8 billion years old, at least in the form we know it to be. Our planet Earth is barely a few billion years old, and life appeared here around 4.5 billion years ago.
But scientists have already known, and for a long time, that water, an element sine qua non to the formation of life as we know it, appeared elsewhere than on Earth long before our blue ball was born. Thus a new study of the cosmological diffuse background, the first radiations of the Universe, made it possible to find traces of water in the primitive galaxies of the Universe more than 12 billion years ago. This find pushes back the presence of water in our Universe by more than a billion years.
Water and carbon monoxide, but no life?
The pair of galaxies observed by scientists known as SPT0311-58 is 12.88 billion years old. At that time the Universe had not yet celebrated its first billion years, it was still at the very beginning of its life. Yet within these galaxies, researchers have managed to find traces of carbon monoxide and water. Two elements which for us, from the Earth, immediately make us think of proofs of the presence of life. But things are actually much more complicated.
So if the presence of water is excellent news from a scientific point of view, the researchers do not want to raise unrealistic hopes with their discovery. Indeed it is more than unlikely that these traces of water are there because life existed in these galaxies. This discovery is nonetheless very interesting. Indeed, the galaxies studied here are among the most massive in the early Universe. They are therefore perfect playgrounds for scientists, who can find molecules in abundance there.