Astronomy 122 Honors, Fall, 2009

Reading and Topics

November 10, 2009. Please read Chapters 16 and 17.

Topics for Chapters 16 and 17

1. Structure of the Galaxy: disk, halo and their differences.

2. Dimensions of Galaxy.

3. The rotation of the Galaxy, the mass of the luminous Galaxy, and the existence of dark matter.

4. The galactic nucleus.

5. Age and evolution of the Galaxy; increase of metal content with time; the role of mergers.

6. Kinds of galaxies: spirals, ellipticals, irregulars.

7. Distances to other galaxies; Cepheid variables.

8. Masses of other galaxies and dark matter.

9. Clusters of galaxies.

10. Active galaxies; the likelihood of massive black holes at the centers of galaxies.