PY 123: Stellar and Galactic Astronomy
An introductory, descriptive survey of stars, galaxies, and cosmology, designed primarily for non-science majors.
The course of Stellar and Galactic Astronomy takes the students into a journey through the Universe from the smallest scale of elementary particles to the largest observable structures, the emphasis being put on stars, galaxies, and cosmology. It presents the currently favored paradigm: the story of a 14 billion-years-old expanding Universe, born in the so-called Big Bang, dominated by mysterious dark energy and dark matter complemented by far less abundant but critically important ordinary matter, enabling star formation and planet formation to happen. It features the main observational discoveries that, coupled with theoretical knowledge, led to this fascinating and surprising picture. The course shows why stars and galaxies emerged from the originally hot and nearly homogeneous Universe, how they are born, how they evolve, how they die.
The course puts forward the concept of scientific theory, its predictive power, as well as its possible falsification by observational discovery. It exposes the Universe as the largest laboratory in which most extreme conditions are met. It illustrates how astronomical observation acts as a strong driver for technology development. But it also attempts to present astronomy, astrophysics and cosmology not only as pure sciences but also as part of the human culture with a strong influence on philosophy and psychology, demonstrating what connects stars and galaxies to the emergence of planets, life, and our existence, what sets our place and time. The course also aims at displaying the images of the Universe as a deep, and largely unexploited, source for artistic inspiration.
The students get acquainted with the currently favored cosmological model and its essential components: dark energy, dark matter, galaxies, stars, radiation. They learn about the history, present, and future of the Universe. In doing so, they also acquire a more general knowledge of laws of nature, their expression through math formulae and equations. They see how critical thinking and observational/experimental testing are essential for testing and falsifying scientific theories and thus for the progress of science.