Astronomers were able to observe closely some of these “cosmic highways” essential to the existence of galaxies.
Galaxies are full of mysteries. What can we still find on the borders of the universe? Astronomers continue to study the formation of the universe and its evolution. With the development of equipment and technologies, new elements are gradually revealed. Long theoretical, the cosmic canvas, for example, is more and more observable. Almost 85% of the universe is made up of dark matter, an invisible substance which does not interact with light, but which is gathering in filaments under the effect of gravity, thus constituting a canvas. Galaxies are formed at the intersections of these filaments, such as a “cosmic highway”.
A new study published in Nature Astronomy Led by Davide Tornotti, a doctoral student at the University of Milan-Bicocca, and in collaboration with the Max Planck Institute of Astrophysics, more closely examined one of these filaments connecting two galaxies. The latter formed when the universe was around 2 billion years and covers nearly 3 million light years. It was observed thanks to an instrument called Muse (Multi-United Spectroscopic Explorer) installed on the very large telescope (VLT) in Chile. Muse makes it possible to capture extremely low light spectra, which is why a high definition image could be produced, which had never been possible before. However, hundreds of hours of observation took to achieve this result.
These filaments are also those which feed the galaxies in gas when they are formed. They therefore transport the raw material necessary for the formation of stars and therefore to the growth of galaxies. “For the first time, we were able to draw the border between gas residing in galaxies and the material contained in the cosmic canvas thanks to direct measures,” explains Davide Tornotti. “By capturing the low light emitted by this filament, which has traveled for a little less than 12 billion years to reach the earth, we were able to characterize its form precisely,” adds the expert.
Researchers now want to study other filaments to have a more complete vision of the cosmic canvas. The long -term objective is to be able to map it as a whole, as well as to test certain theories on the formation of galaxies.