The Earth is the third planet from the Sun and the only known planet to contain life. It is a rocky planet with a liquid inner core, solid mantel, and outer crust. It has an atmosphere made primarily of nitrogen and oxygen and is home to a diverse range of species, including humans. The Earth has a unique magnetic field which protects us from harmful solar radiation, and a gravitational pull that keeps us on the surface. It only has one Moon, called "The Moon", or "Luna" in Latin.