An introductory tour of Earth's cosmic neighborhood -- Largest and smallest scales -- Forces and energy -- Fusion, fission, sunlight, and element formation -- Determination of cosmic and terestrial ages -- Other uses of isotopes for Earth history -- Relative age dating of cosmic and terrestrial evens: the cratering record -- Relative age dating of terrestrial events: geologic layering and geologic time -- Plate tectonics: an introduction ot the process -- Formation of the solar system -- The Hadean Earth -- The Archean eon and the origin of life I: Properties of and sites for life -- The Archean eon and the irigin of life II: Mechanisms -- The first greenhouse crisis: the faint young sun -- Climate histories of Mars and Venus, and the habitability of planets -- Earth in transition: from the Archean to the Protozoic -- The oxygen revolution -- The Phanerozoic: flowering and extinction of complex life -- Climate change across the Phanerozoic -- Toward the age of humankind -- Climate change over the past few hundred thousand years -- Human-induced global warming -- Limitied resources: the human dilemma -- Coda: the once and future Earth.