Natura - nature actualia - actual entities Mundus Plinius - physical world Astra Plinius - celestial bodies Universe (Supercluster) Virgo-Hydra-Centaurus Supercluster (Supercluster) Virgo Supercluster (Cluster) Local Group (Galaxy) Milky Way Galaxy veter. (Spiral arm) Orion Arm (Region) Local Bubble Local Interstellar Cloud (Planetary system) Solar System (Planet-satellite system) Earth System (Planet) Earth veter. "spheres" (Earth) (Sphere) Lithosphere (Earth) - layer of rock "strata" "chronostratigraphic units" "global chronostratigraphic units" (Eonothem) Phanerozoic Eonothem (541.0 Ma - present) (Erathem) †Mesozoic Erathem (252.17 - 66.0 Ma) (System) †Triassic System (251.902 - 201.3 Ma) (Series) †Lower Triassic Series (251.902 - 247.2 Ma) 1 (Stage) †Induan Stage (251.902 - 251.2 Ma) 2 (Stage) †Olenekian Stage (251.2 - 247.2 Ma)