The Sun, Moon, and Earth are three extremely large objects separated by great distances. Despite the large distances between them, each object affects the others. Earth is kept in orbit around the Sun by the gravitational forces between them. The Moon is kept in orbit around Earth by the gravitational forces between them. These gravitational forces are mutual, meaning each object attracts and is attracted by the other. To see how the Sun, Moon, and Earth interact to create tides, in this Activity, you will build a model of the three objects to illustrate the relative positions between them and how these positions change over the course of a month.