Where exactly our own Milky Way and nearby galaxies are actually moving and where they might end up in the next few billion years?
Every major simulation that I’ve used has one problem, it’s very difficult for us to imagine motions of galaxies, as a matter of fact, I cannot think of a single simulation or a single video game even where galactic motion is presented at all.
We’re often presented with what we usually imagine when we think of a galaxy.
Now because of these spiral arms that we see in the Milky Way, we can also imagine that it’s actually spinning, and this is really as far as it goes with most video games and simulations and scientific articles.
We don’t really realize and never even think about that, this and also all those other galactic spots that you see in the night sky background are actually in constant motion and are always moving somewhere.
One day maybe space engine simulator will have this capability of simulating the motion of all of these galaxies we see around us but for now we’re stuck with this still image, almost like a pause button of a video game, where I actually accelerate time but nothing really changes, nothing moves at all, which is very unfortunate.
There is a new study that takes into account pictures that were taken for many years and also analysis of pictures from other studies, that try to estimate based on a red shift and based on radial velocities, where all of these galaxies are actually headed, and as a matter of fact, in this particular study and in the simulation I am about to show you, we can explore to some extent at least where the Milky Way will be headed, where it’s going to end up, and how our nearby galactic neighborhood might actually look like now.
What is known as our galactic neighborhood are the closest galaxies to us here in our cluster, and the most well-known neighbor to us is Andromeda at a distance of about 2.5 million light years.
And then is our neighborhood of about 56 galaxies, most of them small sized galaxies. Only Andromeda the Milky Way and another galaxy known as Triangulum, which is a bit away from Andromeda are the biggest galaxies that we know of. The rest are relatively small also known as dwarf galaxies.
If we were to imagine this as a motion this study from Ed Shaya of the University of Maryland, conducted this research in collaboration with Brent Tully, University of Hawaii, Yehuda Hoffman, Hebrew University in Israel, and Daniel Pomarede, University of Paris-Saclay in France.
This is essentially what the big cluster of nearby galaxies looks like. These are galaxies that we’ve already mapped and are nearby to us except for the region called the main attractor.
In this area of the Virgo cluster is where 600 trillion times the mass of the Sun and about 50 million light-years away from us we are headed.
Andromeda and the Milky Way are actually slowly approaching each other as well and in the next few billion years they’re actually going to collide and turn into one galaxy, and then they’re going to advance and join the Virgo cluster and become a part of a much bigger cluster as well.
At the moment we’re still a little outside of the capture point from the Virgo cluster but in the next few billion years we’re going to approach Virgo cluster close enough that is going to capture us and the motion of our galaxy will actually change, but I guess what’s interesting about these simulations is that you can just manipulate and move around.
It gives you a perspective of how all the galaxies are actually moving, this is how we define galactic clusters nowadays.
When the galaxies are moving towards a similar direction we define it as a local cluster, when big clusters move in the same direction then we define it as a supercluster.
What is really interesting here is that if you were to actually look at all of them over time they’re all moving towards something in our local area, this something is known as the Great Attractor, it’s something that’s supermassive, but we don’t really know what it is so eventually once we join the Virgo cluster we’re going to head in a certain direction.
This is actually before the Andromeda and the Milky Way collide, so this is maybe in about two billion years maybe a bit more, and eventually, in the next two billion years all of these galaxies will actually form a relatively large cluster.
Everything is currently moving in this way and if you look at it again in any simulation you’ll see that most mater is headed toward the Virgo supercluster, but because things are so big in the universe and because our galaxy is gigantic (and other galaxies are even larger), it’s hard for us as humans to imagine this motion.
It’s hard for us to even realize that this is constantly moving somewhere at speeds of hundreds of kilometers per second.
One day some of these galaxies will combine with each other and become even larger, our own Milky Way it’s going to be so massive when it combines with the Andromeda galaxy we’ll reach a point where it’s going to be extremely large.