We Are Part of the Milky Way’s Neighborhood!
Hey there, fellow stargazers! I have an incredibly cool piece of information that I just can’t wait to tell you: Did you know that our Milky Way Galaxy has friends?! I mean, friends like the Andromeda Galaxy and the Triangulum Galaxy! It turns out, our galaxy is part of a little neighborhood of galaxies called the Local Group of Galaxies.
So What is the Local Group?
Think of the Local Group as a small cluster of galaxies all held together by gravity. The Local Group contains approximately 50 galaxies including our galaxy, the Milky Way, the Andromeda Galaxy and the Triangulum Galaxy. Although 50 may seem like a relatively small number when compared to the billions of galaxies in the universe, the Local Group is important in helping scientists understand how galaxies form and evolve throughout the universe.
So Why Does the Local Group Matter?
Galaxies within the Local Group affect one another through gravitational attraction. In fact, the Andromeda Galaxy is moving towards the Milky Way at a very slow rate by Earth standards. However, if we consider that everything in the universe moves at a cosmic speed, then the Andromeda Galaxy is actually moving rather fast. Will they collide? Yes, but not for a couple billion years, so don’t panic!
Why Should We Care About Being in the Local Group?
Being aware that our galaxy is part of the Local Group allows us to get a better idea of the scale of the universe. It takes the seeming endless expanse of the universe and makes it much more manageable. A neighborhood of galaxies where galaxies move, attract to one another through gravity and create the large-scale features of the universe. This realization is also a reminder that the Milky Way Galaxy is not alone in the universe. There is a large cosmic community of galaxies.
In addition to inspiring awe and appreciation for the universe, the Local Group provides astronomers a way to study galaxy formation and evolution, the existence of dark matter and the expansion of the universe. The Local Group serves as a kind of natural laboratory where scientists can study the behavior of galaxies in detail and test various theories about the nature of the universe.
Our Cool Neighbors
Andromeda Galaxy (M31) – Spiral Galaxy Neighbor – the largest galaxy in the Local Group and the nearest spiral galaxy to the Milky Way. It can be seen with the naked eye from earth on a clear, dark night. So you’ve probably looked at it before without realizing it!
Triangulum Galaxy (M33) – Smaller than the Milky Way and Andromeda. This galaxy is known as “the messy” due to its irregular shape. Another popular target for amateur astronomers.
Small Dwarf Galaxies – The Local Group is made up of over 30 small dwarf galaxies that are much smaller than the Milky Way and Andromeda. Most are difficult to detect using even the most advanced telescopes. These dwarf galaxies are important to studying the properties of dark matter and the processes of galaxy formation.
Stargazing with the Cosmos
The next time you are looking up at the night sky and you see a faint fuzzy object, instead of wondering what it could be, think about the possibility that it is a distant galaxy that is one of your Local Group neighbors. We’re all living in the same cosmic neighborhood and are traveling through space and time with billions of stars and numerous unexplored mysteries.
How nice… maybe even wonderful to think about being part of such an active, interconnected environment? We aren’t merely passive observers of the universe; we are inhabitants of one of the more interesting areas of the universe.
Thank you for coming along with me on this little trip through space! Next week, we will explore some of the stranger residents of the Local Group and some of the cutting edge research taking place in our very own galactic backyard. Until then, continue to look up and appreciate the beauty of the massive universe we call home.