Overview:
Class begins with a review of the issues previously addressed about the origin and fate of the universe. The role of gravity in the expansion of the universe is discussed and given as the reason why the rate of expansion cannot remain constant and will eventually slow down. The actual density of the universe is calculated using various methods. Finally, the unsolved problem of dark matter is addressed and two explanatory hypotheses are proposed. One is that the universe is comprised of WIMPs (Weakly Interactive Massive Particles) that fulfill two requirements: they have mass and do not interact with light. The second hypothesis is that dark matter is made of MACHOs (Massive Astrophysical Compact Halo Objects), which scientists have attempted to identify through gravitational lenses.

1. Introduction
2. Planetary Orbits
3. Our Solar System and the Pluto Problem
4. Discovering Exoplanets: Hot Jupiters
5. Planetary Transits
6. Microlensing, Astrometry and Other Methods
7. Direct Imaging of Exoplanets
8. Introduction to Black Holes
9. Special and General Relativity
10. Tests of Relativity
11. Special and General Relativity (cont.)
12. Stellar Mass Black Holes
13. Stellar Mass Black Holes (cont.)
14. Pulsars
15. Supermassive Black Holes
16. Hubble's Law and the Big Bang
17. Hubble's Law and the Big Bang (cont.)
18. Hubble's Law and the Big Bang (cont.)
19. Omega and the End of the Universe
20. Omega and the End of the Universe
21. Dark Matter
22. Dark Energy and the Accelerating Universe and the Big Rip
23. Supernovae
24. Other Constraints: The Cosmic Microwave Background
25. The Multiverse and Theories of Everything

In this course, Yale Prof. Charles Bailyn focuses on three particularly interesting areas of astronomy that are advancing very rapidly: Extra-Solar Planets, Black Holes, and Dark Energy. Particular attention is paid to current projects that promise to improve our understanding significantly over the next few years. The course explores not just what is known, but what is currently not known, and how astronomers are going about trying to find out.



This Yale College course, taught on campus twice per week for 50 minutes, was recorded for Open Yale Courses in Spring 2007.