04 Earth

Earth is the third planet from the Sun and the only astronomical object known to harbor life. About 71% of the Earth's surface is made up of water. The ocean covers most of that area, dwarfing other saltwater and freshwater bodies like lakes and rivers. The remaining 29% of Earth's surface is land, consisting of continents and islands. Much of Earth's polar regions is covered in ice. Earth's surface rests on several rigid tectonic plates, which are slowly moved by an underlying convective mantle layer. Earth's core remains active, generating Earth's magnetic field.