- Although the earth appears to be spherical, its shape is subject to distortions. These distortions occur when the gravitational pull of the moon is strong enough to warp the planet's shape. The moon's gravitational pull acts on all aspects of the Earth's surface, but the pull is too weak to exact large changes in anything other than water. Water's mobile nature allows it to be distorted by the moon's gravity and move across the Earth.
- Due to friction provided by the surface of the Earth and its constant movement, the tides do not follow a uniform pattern. Spring tides are exceptionally strong tides that occur when the sun and moon are aligned and the Earth is positioned directly in the center. This happens with new and full phases of the moon. Neap tides are a product of the sun and moon's gravitational pulls conflicting with each other. These tides are typically weaker and occur when the moon is in its last and first quarter positions.
- While the gravitational pull of the moon is relatively weak, the gravitational relationship of the Earth and the moon will change the movement of the world. Eventually, as in a few billion years, the conflicting gravity will force the Earth and moon into the same rotation. This change will make the moon visible at all times of day from certain areas, as the Earth will always keep the same side toward the moon.
- The sun's gravitational pull, with less then half of the moon's power, still has an effect on tides. This is especially evidenced in neap tides that are dependent solely upon the conflict between the sun and moon. The Earth itself has a hand in tidal changes as its own rotation and angling affects its distance from both gravitational forces.
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