Galaxies and the Milky Way

You may have started this topic thinking that there were just a few galaxies in the universe. Now you know that there are hundreds of billions of galaxies and that they are all classified into two types of galactic clusters. Although all galaxies have the same basic characteristics, they also differ in many ways. The major way that the three basic galaxies differ is their shape, and that is how they are classified.

You also learned that the Milky Way is barred spiral galaxy and has a width of an estimated 100,000 to 120,000 light years. The Solar System is located on one of the many arms in this spiral galaxy. The Milky Way Galaxy formed very similar to the way stars form. Clouds of dust and gas condensed and would eventually create a nuclear bulge near the center. Soon many more clusters of forming stars were gathered and a galaxy was born. It is here, near the center of the Milky Way were the oldest stars are located.

Many questions about the galaxies of the universe remain unanswered. Astronomers learn more and more about the composition, structure, and evolution of galaxies as technology such as the Hubble Space Telescope provides incredible images of different views of the universe.