|AST 307 · Introductory Astronomy
Chapter 24, 25 Nov. 17-21
- Describe the various types of galaxies, in particular comparing
spiral, elliptical, and irregular galaxies.
- Describe two of the variations on the standard candle method which
are used to measure distances to distant galaxies.
- Describe how astronomers measure the distribution of mass within
galaxies, and describe the typical results for spiral galaxies.
How do these measurements indicate that there is unseen, or dark,
matter in galaxies?
- Describe the evidence that galaxies collide or interact with each
other, and the effects of these interactions. Stars almost never
collide with each other. Why are collisions much more common for
- State Hubble's law. Say how Hubble's constant is measured.
Why doesn't Hubble's law apply to objects in the solar system or
in the Milky Way?
- Describe two types of active galaxies and say how they differ
from normal galaxies like the Milky Way.
- Describe a theory about how active galaxies could have formed.
What makes us think that active galaxies have supermassive
black holes in their nuclei?