What Causes the Tides and Why Do They Change?

Imagine Earth is like a giant sponge, and the Moon is a big magnet. When the Moon pulls on the sponge (Earth), it stretches it out, making the water rise, that's high tide! When the Moon moves away, the water falls back, that's low tide. The Sun also helps with this tug-of-war, which makes tides change all day long.

Why Do Tides Change?

Sometimes the Moon and the Sun pull in the same direction, making really big tides called spring tides. Other times they pull in opposite directions, giving us smaller tides called neap tides.

Take the quiz →

Examples

Imagine a big rubber ball (Earth) being pulled by a magnet (Moon), causing the ball's surface to stretch, that's how tides work!
If you fill up a glass of water and move your hand around it, the water will bulge toward your hand, like how the Moon affects the ocean.
When both the Sun and Moon pull in the same direction, it’s like two people helping you lift something, making the tide bigger.

Ask a question

Discussion

Recent activity

Categories: Science · tides,moon,gravity,oceanography