Although there are many types of galaxies in the universe, we will be focusing on the three main types.
Spiral Galaxy
- a flat disk with bulging center and surrounding spiral arms.
- Many of the new stars form in the spiral arms
- Many of the older stars reside in the center of the galaxy.
- Edwin Hubble first described this type of galaxy.
- Most of these galaxies have a "Bar", or arms extending from the central bulge only.
- The Milky Way is a "Barred Spiral" Galaxy.
Irregular Galaxy
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Elliptical Galaxies
- They have a "spotless" profile
- Spherical
- Very bright: their stars orbit around the center
- More three dimensional
- Mostly contain low mass stars
- Very uncommon type of galaxy
- Found less commonly in the "Early" universe
The video below is about the Sun compared to the whole universe inside the Milky Way.
Quiz
1. A galaxy with arms forming from the center.
2. A galaxy with a "spotless" appearance.
3. A galaxy found less commonly in the "early" universe.
4. Usually orbit other galaxies.
5. The most common type of this galaxy is a "Barred" type.