What is Earth

Earth is the third planet from the Sun and the only known planet to have life. It is a terrestrial planet with a diverse environment,

 including oceans, mountains, deserts, and forests. The Earth has a diameter of about 12,742 km and is the fifth densest planet in the Solar System. It is primarily composed of rock and metal, with a relatively thin atmosphere composed mostly of nitrogen and oxygen. Earth has a magnetic field which protect life on earth from harmful solar radiation. The planet has one natural satellite,

 the Moon. Life on Earth is diverse and ranges from single-celled organisms to complex animals and plants. Humans, one of the most advanced forms of life on Earth, have greatly impacted the planet through activities such as agriculture, industrialization, and urbanization.