Defining the difference between astrophysics and astronomy; studying the vast range of scales in astrophysics; getting the big picture in a breathtaking series of exponential jumps from the Earth to countless clusters of galaxies.

Zooming in on the microcosmos; why elementary particles are just as central to astrophysics as stars and galaxies; reviewing the four fundamental forces of nature; performing a calculation that explains why atoms have to be the size they are.

How astrophysicists map the universe; focusing on the tricky problem of calculating distances; how a collection of overlapping techniques provide a "cosmic distance ladder" that works from nearby planets to stars and far distant galaxies.

Discovering the law of gravity just as Newton might have; analyzing Kepler's laws with the aid of calculus; a graphical method for understanding orbits; the conservation laws of angular momentum and energy in light of Emmy Noether's theory.

Learning why the rings around Saturn and the much fainter rings around Jupiter, Uranus and Neptune are roughly at the same relative distances from the planet; knowing why large moons are only found in wide orbits; an analysis of tidal forces.