An expected phenomenon, which science had theorized, but until now had not been able to be observed. For the first time in history , an international team of astronomers led by the Instituto Astrofísico de Canarias (Spain) has detected, thanks to the Gran Telescopio de Canarias located at the Roque de los Muchachos Observatory (La Palma), several galaxies feeding directly on gas from the cosmic web .
In this event, in which galaxies grow and form stars from gas, an extra supply of matter is necessary , since the amount of gas they possess is quite limited to be able to remain active throughout the life of the universe. That is why the experts had theorized that the gas that nourished them must come from the cosmic network, that is, the original gas produced in the Big Bang and distributed in space through this kind of network of filaments. Now, it is a fact: “finally a direct proof has been found ”, comments Jorge Sánchez Almeida, co-author of the study.
“ In some galaxies we observe regions where the star-forming gas is primordial. It is made up almost exclusively of hydrogen and helium, and this type of pure gas is very rare in a galaxy ”, explains Casiana Muñoz, co-author of the study.
The researchers analyzed the chemical composition of rather faint galaxies, finding in some the polluted gas produced by the stars – with oxygen or carbon – and the uncontaminated gas, which “must necessarily come from the cosmic web . We have not found another reasonable explanation ”, clarifies Muñoz.
The research has been published in the Astrophysical Journal Letters.
