Galaxies and the Milky Way

Image Courtesy of NASA

When you look at the picture to the right, you may think all of those glowing objects in the image are stars. Guess again! Each one of those objects is a separate galaxy.

Galaxies are a group of stars, dust, gas, and planets held together by gravity. You may have noticed from the image that not all galaxies have the same shape. You will find that galaxies are classified according to their shapes. Galaxies like the Milky Way have a spiral shape. The most common shape for a galaxy is like a football, or elliptical. Other galaxies have very irregular shapes, or no defined shape. No matter what shape, each galaxy has its own special properties and characteristics. In this topic, you will investigate the three major types of galaxies and learn the properties of each type. Also, you will learn more about your own galaxy, the Milky Way.

Essential Questions

  • What are the properties of each type of galaxy?
  • What is unique about the Milky Way Galaxy?