Liked on YouTube: Voids And Supervoids: The Weird Part Of The Universe!

Voids And Supervoids: The Weird Part Of The Universe!
If you have ever watched a starry sky at night from a remote location, far away from any city and not affected by light pollution, you may have remained astonished by the huge amount of stars that cover the sky. In fact, you may have been thinking that the Universe is probably a place very dense of stars and galaxies. This is somehow true, but… only in some parts of the Universe. In fact, while galaxies are quite rich of stars, the space between galaxies is generally empty. And sometimes, these intergalactic spaces can reach enormous sizes, forming huge regions of Universe that are almost completely dark and empty! These regions are known as “voids” and “supervoids”. You want to hear more about them? Watch this video and I will tell you more! ------------------------------------------------------------------------------------------- Subscribe for more videos:https://www.youtube.com/c/InsaneCuriosity?sub_confirmation=1? Business Enquiries: lorenzovareseaziendale@gmail.com ------------------------------------------------------------------------------------------- While you watch a spectacular starry sky at night, you may think the Universe is quite uniform, with stars and galaxies scattered all around with no particular differences between one region and another. That is not actually true! In fact, the structure of the Universe is quite weird. Let’s start our journey from a small scale, and then we will enlarge our vision to see what happens at bigger scales. As you know, stars are grouped into galaxies, which is a concept you are probably familiar with. Galaxies contain an enormous number of stars: hundred millions, some of them even hundred trillions! In fact, all the stars you see in the sky are part of our galaxy: the Milky Way. While galaxies are very huge objects, the distance separating them is even larger. For instance, while the Milky Way has a diameter of about 100,000 light years (remember: one light year is the distance covered by light in one year), the closest galaxy, Andromeda, is 2.5 million light years away: it’s about 25 times the size of the Milky Way. But despite these numbers being already very large, galaxies are still quite close to each other, in astronomical terms. In fact, galaxies tend to “gather” into groups, due to the effect of the force of gravity bringing them together; these large groups are called “clusters”. The Local Group, the cluster where the Milky Way is located, contains about 100 galaxies. And the story goes on: these clusters are gathered into even larger structures, known as “superclusters”, containing thousands of galaxies. Here it’s where things get pretty big. Gravity is always the driving force that shapes the Universe, and it keeps playing its role at this level as well. In fact, even these superclusters attract each other. However, at this point they do not gather into “megaclusters” or something like that, rather into longer, thin structures known as “filaments”. In fact, if we could look at the Universe at this scale, it would look like a gigantic spider web (but without that regular geometric pattern!), with these filaments corresponding to the strings of the net. So, we now know how the Universe looks like at its largest scale, at least as far as we know. These filaments are massive structures, spanning over million light years. But what’s in the space between the strings of this huge spider web? Is there anything between these filaments? That’s where things get more intriguing, and that’s where we reached the main topic of this video: these spaces between filaments are those called “voids” and sometimes “supervoids”! What are they? To understand what voids and supervoids are, we have to talk about density first. Density is a physical quantity describing the amount of matter in a fixed volume. If we look at a smaller scale, density tells us how close are atoms and molecules to each other in an object or a substance. Higher density means that the atoms and molecules are closer to each other, and so there is less empty space between them. Now we can apply this concept to a larger scale: the Universe. But in this model, the atoms are replaced by galaxies. Different regions of the Universe have different densities: while most galaxies are concentrated in the filaments, voids are almost completely empty. In fact, the density of these voids is less than one tenth of the average density of the rest of the Universe. Therefore, these voids are big regions of space relatively empty, containing very few galaxies compared to clusters and superclusters. Some of these voids can even “merge” together forming huge ones, which are sometimes referred to as “supervoids”. The biggest known supervoid, the Boötes void, has a diameter of about 330 million light years: it’s more than 3000 times the size of our galaxy! It’s no coincidence that it is sometimes called “the Great Nothing”. #InsaneCuriosity
via YouTube https://www.youtube.com/watch?v=I4Yc8Zw_NJo