Did you know that the earth does one revolution around the sun every year? The gravitational pull of the sun (which is a star by the way!) is what keeps the earth and all other planets in orbit. As the earth is orbiting around the sun the moon is orbiting around the earth! It takes about 27.25 days or about a month for the moon to go around the earth once. The earth’s gravitational pull keeps the moon in orbit and the gravitational pull of the moon causes the high and low tides of earth’s oceans each day.