Gravity causes Earth tides by the gravitational force between the Moon and the Earth. The Moon's gravitational pull creates two tidal bulges on opposite sides of the Earth, one facing the Moon and the other on the opposite side. As the Earth rotates on its axis, different parts of the planet pass through these tidal bulges, which leads to the rising and falling of the water level, creating high and low tides. The Sun also affects the tides, but to a lesser extent, due to its greater distance from the Earth.
