The Moon’s Shape-Shifting Secret!

Hi, little stargazers!

Have you ever looked up and seen the moon looking like a big round cookie one night, then a tiny sliver the next? Does it really change shape? Nope—it’s a trick! The moon stays the same, but we see it differently because of the sun.

The moon doesn’t make its own light—it’s like a big mirror reflecting sunlight. As it travels around Earth every month, the sun lights up different parts of it. When the whole side facing us is bright, we see a full moon. When only a little edge is lit, we see a crescent. It’s like the sun playing peekaboo with the moon—and we get to watch!

The moon’s trip around Earth takes about 28 days, and that’s why its shape seems to change a little every night. It’s not magic—it’s just sunlight and shadows!

Try This Moon Shape Experiment!

Want to see how the moon’s shapes work? Let’s make our own moon!

What You Need:

• A small ball (like a tennis ball or an orange—to be your moon)
• A flashlight (the sun)
• A dark room
• You (to be Earth!)

What to Do:

1. Turn off the lights in a room to make it dark like space.
2. Hold the ball in front of you at arm’s length—that’s your moon.
3. Ask a friend or grown-up to shine the flashlight from one side—like the sun shining on the moon.
4. Look at the ball. What part is lit up? Turn slowly in a circle while holding the ball, keeping it in front of you.
5. Watch how the light on the ball changes. Can you see a full circle, a half, or just a sliver?

What You’ll See:

As you turn, the lit part of the ball changes! From a full bright circle to a thin crescent—just like the moon. That’s how Earth’s view of the moon shifts as it orbits.

Why It Works:

The moon doesn’t change, but the angle of sunlight hitting it does. When you turn, you’re like Earth spinning, seeing different lit-up parts of the moon. That’s the secret of its shapes!

You’re a moon expert now! Next time you spot the moon, guess what shape it’ll be tomorrow.

What’s your favorite moon shape?