Our galaxy and the rest of our cosmic environment are on the edge of a colossal void that is more than 1 billion light-years long and contains “nothing.” That is the main and surprising conclusion that a team of cosmologists has made at the annual meeting of the American Astronomical Society in Austin, Texas (USA).
In a previous study of 2013, astronomer Amy Barger of the University of Wisconsin-Madison , and his then student Ryan Keenan showed that n ur galaxy, in the context of large – scale structure of the universe, resides in an enormous vacuum, this is , an area of space that encompasses far fewer galaxies, stars, and planets than it should.
Now, a new study from the same university not only reaffirms that idea that we live in one of the holes in the cosmic cheese that is the universe, but also helps facilitate the apparent disagreement between the different measurements of the Hubble Constant , a unit that cosmologists use to describe the rate at which the universe is currently expanding. And the results vary according to the technique used to measure the expansion of the universe (the Cosmic Microwave Background technique or the supernova technique).
“No matter which technique is used, we should get the same value for the current expansion rate. Fortunately, living in a vacuum helps resolve this disagreement,” says Ben Hoscheit, leader of the current work.
The new report is part of a much larger effort to better understand the large-scale structure of the universe. In this sense, the structure of the cosmos would have the shape of Gruyere cheese , since it is composed of “normal matter” that is distributed in holes and filaments. Filaments are made up of superclusters and clusters of galaxies, which in turn are made up of stars, gas, dust, and planets. The remaining 95% would be made up of dark matter and dark energy.
Thus, this huge void in which we find ourselves is at least seven times larger than average, with a radius of approximately 1 billion light years. Therefore, it is the largest void known to science so far.
The new analysis shows that there are no observational obstacles to the conclusion that the Milky Way resides in a very large vacuum. Furthermore, the presence of a vacuum can also resolve some of the discrepancies between the techniques used to measure the expansion rate of the universe, as we have just seen.
