Astronomy 100
Section 2, Fall 2008
Topics and Reading
Unit 9. November 19, 2008. Galaxies and the Universe
Reading
- Text: Chapter 11
- Text: Chapter 12
Topics
1. Structure of the Galaxy: disk, halo and their differences; the
likely nature of the nucleus.
2. Dimensions of Galaxy.
3. The mass of the luminous Galaxy and the existence of dark
matter.
4. Age and evolution of the Galaxy; increase of metal content with
time; the role of mergers.
5. Kinds of galaxies: spirals, ellipticals, irregulars.
6. Distances to other galaxies; Cepheid variables.
7. Masses of other galaxies and dark matter.
8. Clusters of galaxies.
9. Active galaxies; the likelihood of massive black holes at the
centers of galaxies.
10. The velocity-distance (Hubble) relation; the meaning of the
redshift, z, and the expansion of the Universe.
11. The Big Bang, the Hubble constant, and the age of the
Universe.
12. The cosmic background radiation.
13. Expansion models. The curvature of the Universe.
14. The origin and evolution of the Universe; formation of
galaxies.
15. Acceleration of the expansion and dark energy.