Today, we’re going to do an experiment that shows why the moon has craters and then I’ll give you an extension that shows why the earth doesn’t have as many. This is a quick, easy science experiment that uses ingredients you probably have around the house.

This experiment was inspired by the book When The Shadbush Blooms. If you’d like to explore more moon activities, look for the When The Shadbush Blooms activity packs in my store.

Are your kids going through a science exploration phase? Or an astronaut phase? I think many kids have a phase like that and it’s fun to watch their curiosity move in that direction.

But sometimes, that space phase leads to questions we have no stinking idea how to answer. I don’t know why black holes don’t suck us all up. I don’t know how many years we have until the sun implodes. I don’t know what the gas on Saturn smells like.

If you’re struggling with tricky space questions, I’m here to give you an easy win! I DO know why the moon has craters and in about 15 minutes, you will too! Let’s get started!

Image shows supplies needed for this exploration
Simple ingredients you probably have at home.

Supplies:

  • 4 cups flour
    • Any kind will work
  • ½ cup baby oil
    • You can get this in the baby hygiene section of the supermarket
  • A large bowl
    • Something to mix your moon in
  • Small rocks or pebbles
    • Nothing too big, we don’t want to have a catastrophic event!
  • A round pan or dish with sides
    • You’ll need sides to hold your moon in!
  • If you’re going to do the moon/earth comparison, you’ll also need:
    • A thin piece of bubble wrap or pillow type packing material

Step 1: Make Cloud Dough

Image show a pair of hands mixing flour and baby oil into cloud dough
Don’t be afraid to get your hands dirty!

Before we can find out why the moon’s surface is bumpy, we have to make our moon!  To do that, we’re going to make cloud dough.

 Put 4 cups of flour in your bowl.  Then add ½ cup baby oil. After you’ve added your baby oil to your flour, get your hands in there and mix it up!  At first it’s going to be gooey and kind of gross, but keep mixing.  It will eventually get soft and fluffy! When you get to the point where you can make a fist around some dough and it holds together, your cloud dough is ready.

Step 2: Make The Moon

Image shows a hand pouring cloud dough from a bowl into a round dish.
You may not need all your cloud dough.

Take your round pan or dish.  Carefully pour your cloud dough into it.  Use your hands to gently even it out.  We’re going to pretend this is the moon’s surface.  

Step 3: Drop Meteors

Image shows a hand holding a pebble above a smooth, cloud dough surface, ready to drop it.
Experiment with different ways to drop your pebbles. What happens if you drop them from higher up? What if you push harder when you drop?

I don’t have extra meteorites laying around my backyard, so we’re going to use pebbles instead.

Let’s take our pebbles or “meteorites”.  Hold them above the moon and drop them. 

What happened?  Carefully pick up your meteorite.  What do you see?  It’s a crater! The surface isn’t smooth anymore. 

Keep dropping meteorites and picking them up.  Now our pretend moon looks a lot like the real moon, doesn’t it?

Meteorites are the reason the moon’s surface is covered in craters!

Step 4: Compare to Earth (optional)

As a cool extension, you can do the same experiment, but add the bubble wrap or packing material on top of your “surface”. This will act like our atmosphere and protect the surface of the Earth from the Meteors.

The packing material analogy isn’t perfect because the pebbles will likely bounce off the surface, but it gives a good illustration of how our atmosphere protects Earths surface and why the atmosphere free Moon has many more craters.

A better illustration might be something like jello poured over the top of the cloud dough, but honestly, that just sounds like a messy disaster to me. If you are a braver person than I, pour the jello over your surface, let set, and then drop craters with abandon. Good on ya’!

Wouldn’t this be a cool science fair project? Your student could drop a set number of rocks on the Moon’s surface, drop the same number on Earth’s protected surface, and present the results. So cool!


A couple of vocabulary words that I covered in the YouTube video that are good for kids to know:

Craters

     Crater is a fancy word for a huge bowl shaped dent in the surface of a moon or planet. 

   There are craters all over the moon and we also have some craters here on Earth.

Meteorite

      Meteorite is a fancy word for an object, usually a rock, that comes from space and hits the surface of a planet or moon.  Meteors are what meteorites are called before they hit the surface.

Lunar 

 Lunar  is a fancy word that means moon.  When we talk about the lunar surface, that just means The Moon’s surface.

Atmosphere

Atmosphere is the fancy word for the big bubble of gas that surrounds Earth.  The moon does not have an atmosphere and thus has nothing to protect it from incoming meteors.


Thanks for coming along today as we explored the moon’s surface and why it has craters. I publish a new science experiment or craft blog and video every week. Subscribe to my YouTube channel to see what fun things we’re doing next!

Idea adapted from icanteachmychild.com