Imagine you are an astronaut looking down on Earth Earth as you circle planet in your spacecraft. From this height, Earth looks small and round. White clouds swirl around the planet, making it resemble a marble. The deep shades of blue that you see are mainly water. Earth has four main bodies of water, or oceans. They are the Pacific, the Atlantic, the Indian, and the Arctic oceans. The oceans are connected to form one vast body of water that covers much of Earth. In places you can see large land masses interrupting the oceans. These land masses are the seven continents of Earth. The continents are North America, South America, Africa, Asia, Europe, Australia, and Antarctica. Most of Earth's people make their homes on the continents. The people of the United States, for example, live on the continent of North America. Nigerians live in Nigeria a country on the continent of Africa.