Spring tides occur when the moon is full or new. Earth, the moon, and the Sun are in a line. The moon’s gravity and the Sun’s gravity pull Earth’s crust and ocean water. This causes tides to be higher than normal.

At neap tide, the moon and the Sun are at right angles to each other. This happens during the first and third quarters of the lunar cycle. At neap tide, the Sun’s gravity and the moon’s gravity are balanced. High tides are lower; low tides are higher.

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High and low tides are caused by the Moon. The Moon's gravitational pull generates something called the tidal force. The tidal force causes Earth—and its water—to bulge out on the side closest to the Moon and the side farthest from the Moon. These bulges of water are high tides.

Explanation:

When the sun, moon, and Earth are in alignment (at the time of the new or full moon), the solar tide has an additive effect on the lunar tide, creating extra-high high tides, and very low, low tides—both commonly called spring tides.

More Tidal Facts:

One cycle of tides actually takes 24 hours and 50 minutes. The highest tides occur when the Moon is new or full. High tides sometimes occur either before or after the Moon is straight overhead. Sometimes there are really low tides called neap tides. Some places have only one high tide and one low tide in a cycle (24 hours and 50 minutes).

Sample Response: Spring tides occur when the moon is full or new. Earth, the moon, and the Sun are in a line. The moon’s gravity and the Sun’s gravity pull Earth’s crust and ocean water. This causes tides to be higher than normal.

At neap tide, the moon and the Sun are at right angles to each other. This happens during the first and third quarters of the lunar cycle. At neap tide, the Sun’s gravity and the moon’s gravity are balanced. High tides are lower; low tides are higher.

Explanation:

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