The third planet from the sun is Earth. It is the only planet known to support life, due to its unique conditions, such as the presence of liquid water, a breathable atmosphere, and the appropriate distance from the sun for temperatures that can sustain life. Earth has a diverse range of ecosystems, including oceans, forests, deserts, and mountains. The planet has a rich history, with its geological and biological evolution shaping the environment we see today. Earth is also home to billions of species and diverse cultures, making it a dynamic and complex planet in our solar system.