First Images Of The “Cosmic Web” Hint At Billions Of Undiscovered Dwarf Galaxies

Large, much larger than a galaxy, matter is distributed in a filamentary structure in the universe we call the “cosmic web”. It is a huge network of galaxies connected together by intergalactic gas.

Gas fibers are not easy to observe and only we have recently been able to study them directly. Now, for the first time, astronomers have observed several filaments of the cosmic web at once. As reported in Astronomy and Astrophysics, the observations required an incredible 140 hours of observation in a single small region of the sky using very large telescopes (VLTs) and its MUSE (Multi-Unit Spectroscopic Explorer) instruments. When the universe was only 1.3 billion years old, the farthest flames observed were. The nearest was 800 million years later.

This was an important time for the universe as the galaxies they were creating and growing at incredible speeds. The area observed in this ambitious expedition is already famous. It is part of the Hubble Ultra Deep Field. The region observed by the Hubble Space Telescope from late 2003 to early 2004. Since then it has been repeatedly refined and remains the deepest image of the universe of all time. New observations extend extensively into it. Astronomers have previously estimated that about 10,000 galaxies are visible in this region of the sky. Destined increase the number. In parts of the Ultra Deep Field studied by the team, the number is more than 40 percent. In addition, that is not all. We probably do not see that there are many more galaxies.

The team hired a simulation to work on what is illuminating the gas filaments of the cosmic web. The gas of these interconnected connections is highly scattered so if we can see it is illuminating. One answer to the simulation was for the team. There are plenty of galaxies out there. Studies have shown that billions of dwarf galaxy populations are illuminating these filaments. However, these are very few to see and ignorant. “We think that the light we see comes mainly from young galaxies, each with millions of times fewer stars than our own Milky Way.

Co-author Joop Schaye from Leiden Observatory said in a statement, these tiny galaxies were probably responsible for the end of the cosmic ‘dark age’, when, less than a billion years after the Big Bang, the universe was illuminated and heated by first-generation stars.” This finding will certainly start a big debate on the field. The most common hypothesis for the source of illumination believed to be a diffuse cosmic ultraviolet background produced by young stars in galaxies. It will light up and illuminate them. However, more observation need better understand the mysteries of the cosmic web.