In this project, you'll create your own solar system out of playdough to learn how the planets formed.

Photo of the materials for this activity.


1. Get to know our solar system

Get to know our solar system and what makes it so special by visiting NASA's Solar System Exploration website and exploring the interactive below. Consider the diversity of celestial bodies in our solar system beyond the eight planets, such as the moons, asteroids, comets, and dwarf planets. Each has unique characteristics.

This interactive shows a real-time simulated view of the solar system and NASA missions in space. Explore more by clicking and dragging or use the control icons.

Photo of the process described in step 2.

2. Form a nebula

Roughly 4.5 billion years ago, our solar system formed from a nebula made up of interstellar dust and gas.

Start your model by creating this ancient nebula. Use one color of playdough to create 15-20 pea-size balls, and place them on your paper plate. These represent interstellar dust.

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Photo of the process described in step 3.

3. Add new elements

The interstellar dust that gave rise to our solar system was made up of a wide range of elements from the periodic table.

We'll simulate these different types of dust by adding 15-20 more pieces of playdough in different colors. Try using three to four different colors to best represent the variety of interstellar dust.

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Animated image of the process described in step 4.

4. Introduce orbital motion

The elements of our solar system are not stationary. They are constantly orbiting our Sun at dozens of kilometers per second.

Introduce this movement in your early solar system by using your hand to gently apply pressure to your plate. Now, move your hand clockwise around the "solar system" (plate) three or four times.

What did you observe? Do you have the same number of pieces as before? You may notice that some pieces are now stuck together. This process of the pieces coming together is called accretion. It's what creates planets and other celestial bodies. While accretion happened quickly in our model, the process took place over billions of years in our solar system.

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Animated image of the process described in step 5.

5. Repeat the process

Repeat the process of gently moving your hand over the model solar system another three or four times.

What happened to the pieces of dust over time? Did you have as many pieces collide and form larger planets this time? You may have noticed that you had fewer collisions. This is because your newly formed planets had already picked up all the dust in their orbital path. Now, your model solar system is starting to look more like the solar system we have today.

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Photo of the process described in step 6.

6. Notice different types of planets

Looking at your solar system model, what do you notice about the colors of playdough in each new planet? Are they all the same color? The same amount of each color? Likely you'll notice that each of your planets looks a little different, some having more of each color than others and some being larger or smaller.

Similarly, our solar system is made up of many types of celestial bodies, ranging from small rocky planets like Earth to gas giants like Jupiter.

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7. Add the energy of our Sun

Thanks to the heat and solar wind from our Sun, elements in our early solar system were not randomly distributed the way they might have been in our first model. Volatile gasses were sent past the asteroid belt to a cooler area of space, while rocky materials were drawn in by the Sun's gravity.

Recreate your solar system model from the beginning with colors arranged by distance from the center. What happens to your planets this time? Are they all made up of similar elements or are the elements mixed together, and where?