THEMESTimeMeasuring the Ages of RocksEra IntrosEra RecapsSpace!The Origins of the EarthThe SunThe MoonAll Space-Themed EpisodesEarth’s StructureThe Origins of the EarthThe Interior: Mantle and CorePlate TectonicsEarth’s SurfaceWater and Oceans“Dry Land”Atmosphere and ClimateRock TypesIgneousSedimentaryMetamorphicLife and FossilsOrigins of LifeDisputed Fossils