Here's why:
* Gravitational Influence: The moon's gravity pulls on the Earth's oceans, creating bulges of water on the side facing the moon and the opposite side.
* Sun's Influence: The sun also exerts a gravitational pull on the Earth, though it's weaker than the moon's because it's much farther away.
* Alignment: During a full moon and new moon, the sun, Earth, and moon are aligned, meaning their gravitational forces combine to create a stronger pull on the oceans, resulting in higher tides called spring tides.
Last quarter moon (and first quarter moon) experience neap tides, which are lower than average high tides because the sun and moon are at right angles to each other, their gravitational forces partially cancel each other out.
