This course will introduce students to the basic concepts of Einstein's General Theory of Relativity. Several observational tests of general relativity will be discussed. Both special and general relativity will be applied to the study of neutron stars, black holes, gravitational waves, gravitational lenses, and time machines. The second half of the course will be devoted to cosmology, covering topics such as the Big Bang, the very early evolution of the universe, including the inflationary scenario and nucleosynthesis, and formation of galaxies and large-scale structure of the universe. Observational results from satellites, including the Cosmic Background Explorer, the Hubble Space Telescope and the Chandra X-ray Observatory, will be discussed, as well as future plans for mapping the primordial background radiation in even more detail than current knowledge. This course will not be heavily mathematical; the required mathematics will be developed as needed. Format: lecture/discussion, three hours per week. Evaluation will be based on homework assignments, two hour exams, and a final exam. Prerequisites: a 200-level Physics course; or permission of the instructor.