Day and night, the seasons, the stars through the year, the Moon's phases and eclipses, gravity and orbits, and the true scale of the solar system, measured with the numbers an astronomer uses.
Orbits and gravity, light and telescopes, the solar system, the Sun and the stars, how stars live, die and make the elements, galaxies and the Big Bang, and the search for life, measured with the numbers astronomers use.
Stars derived from physical law: radiation and magnitudes, stellar atmospheres, structure and nuclear energy, how stars evolve, white dwarfs, neutron stars and black holes, the interstellar medium, and the dark matter and black holes of galaxies.
The expanding universe from its evidence: Hubble's law and the distance ladder, the Friedmann equation, curved space and cosmological distances, the microwave background and the first elements, dark matter and dark energy, and the growth of structure and inflation.