Growing up as an avid space buff I have enjoyed the ever changing understanding of the Milky Way Galaxy. Oddly enough science has had a much easier time understanding other galaxies because they are easier to see. It is much like determining the size of a forest while standing in the middle of one. There is a lot of trees and hills in the way.
For the past ~150 years the idea has been around that the Milky Way was a spiral galaxy much like the nearby Andromeda Galaxy.
Pictures of the Andromeda were probably used many times to show what scientists thought the Milky Way looked like. Even today finding pictures of the Milky Way like this are easy to find.
They also happen to be incorrect. We live in a different type of galaxy.
Back in 2004-2005 the idea started to show up that the Milky Way was a spiral galaxy with a bar in the center. The pictures that popped up from idea have become the popular new pictures of the galaxy.
Even this has changed now. The most recent news about the Milky Way is that it is a true bar galaxy with only two spiral arms coming off each side of the central bar. Not only that but the other arm is slightly bent, not that such a bend would be visible in a picture. This bend matters because in astronomy if you look where you expect something to be and it isn’t there, then you have to revise your idea. The bend could explain why there has been so much difficulty in defining the precise shape of the Milky Way.
If the latest paper is correct, then the actual shape of the Milky Way would be much more similar to what is known as the Great Barred Galaxy, affectionately known to astronomers as NGC 1365. If that is the case then what our galactic home looks like would be much more like this.