Earth is the third planet from the Sun and the only astronomical object known to harbor life. This is made possible by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is contained in its ocean, which covers 70.8% of Earth's crust. The remaining 29.2% of Earth's crust is land, which is predominantly located within Earth's land hemisphere in the form of continental landmasses. Most of Earth's land is at least somewhat humid...
