The author traces human star-worship and calendrical uses of celestial observation, then surveys the Milky Way’s structure and nebulae, stellar classification, and theories of stellar motion and evolution. He examines the climatic importance of water vapor and atmospheric physics, considers atmospheres and spectra of planets and moons, and discusses solar-system formation from nebular material and the long-term fates of stars and planets. Essays combine historical, observational, and theoretical perspectives to connect cultural astronomy, planetary environments, and cosmological processes, offering interpretations of how stellar and planetary evolution shape climates and the possibilities for life.