1. Sombrero Galaxy
Galaxies are sprawling space systems composed of dust, gas, and countless stars. The number of galaxies cannot be counted—the observable universe alone may contain 100 billion. Some of these distant systems are similar to our own Milky Way galaxy, while others are quite different. Galaxies with less than a billion stars are considered ‘small galaxies.’ In our own galaxy, the sun is just one of about 100 billion stars.
This is a spiral galaxy seen nearly edge-on. The dark band across the center is the result of material in the flat disk of the galaxy obscuring the light of stars and gas behind it. The glowing bulge holds a population of stars largely different those in the flat disk. Look close to see numerous globular clusters, which appear as slightly fuzzy stars, each of which is itself composed of many hundreds of thousands of stars.