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) Biosphere (Earth) - zone of life "marine ecoregions" (Biogeographic realm) Arctic 01 (Marine ecoregion) North Greenland 02 (Marine ecoregion) North and East Iceland 03 (Marine ecoregion) East Greenland Shelf 04 (Marine ecoregion) West Greenland Shelf 05 (Marine ecoregion) Northern Grand Banks–Southern Labrador 06 (Marine ecoregion) Northern Labrador 07 (Marine ecoregion) Baffin Bay–Davis Strait 08 (Marine ecoregion) Hudson Complex 09 (Marine ecoregion) Lancaster Sound 10 (Marine ecoregion) High Arctic Archipelago 11 (Marine ecoregion) Beaufort–Amundsen–Viscount Melville–Queen Maud 12 (Marine ecoregion) Beaufort Sea—continental coast and shelf 13 (Marine ecoregion) Chukchi Sea 14 (Marine ecoregion) Eastern Bering Sea 15 (Marine ecoregion) East Siberian Sea 16 (Marine ecoregion) Laptev Sea 17 (Marine ecoregion) Kara Sea 18 (Marine ecoregion) North and East Barents Sea 19 (Marine ecoregion) White Sea