While people have puzzled about their place in the universe for thousands of years, scientific cosmology dates from the 1920s, when Edwin Hubble discovered the expansion of the universe. This course explores, in a generally qualitative fashion, the evidence of the creation of the universe in the Big Bang and the evolution of the universe with time. Various cosmological models that explain important observations about the universe's large-scale structure are compared to illustrate not only the science involved but how scientific research evolves when old models and theories are unable to explain new data.
The course includes the origin of the simplest chemical elements shortly after the Big Bang, the condensation of matter in the early universe into large structures such as galaxies and clusters of galaxies, and scenarios that explain why we find different types of galaxies in the universe. The Milky Way is used as a specific example of a spiral galaxy to examine how matter is cycled from the interstellar medium into stars that evolve and eventually die, putting their matter back into the interstellar medium. This process creates more complex elements, including those necessary for life as we know it.