ABSTRACT
A brief overview of astronomy and cosmology is presented in five different ways, through the
lenses of space, time, evolution, process, and structure. Specific topics are chosen for their con-
tribution to a “big picture” understanding of the interconnectedness of knowledge in astronomy
and cosmology. us, many topics (stellar astronomy for example) are treated in multiple sec-
tions, but from different viewpoints—for example, sizes and distances of stars (space); when stars
appeared in the history of the universe (time); stellar evolution (evolution); hydrostatic equilib-
rium and stellar spectra (process); and stellar structure (structure). Some topics traditional to the
introductory astronomy curriculum—eclipses and lunar phases, for example—are omitted alto-
gether as they are inessential for the big-picture goals of the book, and excellent summaries are
easily available elsewhere. On the other hand, the book treats some topics not usually covered
in an introductory astronomy course, for example the roles played by equilibrium processes and
symmetry in our understanding of the universe. e level is for the beginning undergraduate,
with only basic skills in rudimentary algebra assumed. But more advanced students and teachers
will also find the book useful as both a set of practical tools and a point of departure for taking
stock (in five different ways) of the current state of knowledge in astronomy and cosmology.
KEYWORDS
astronomy, cosmology, evolution, stellar spectra, hydrostatic equilibrium