STEM Activity: Make Your Own Lunar Rocks

International Moon Day, observed on July 20, celebrates the historic moment in 1969 when humans first set foot on the moon.

During this landing, 800 pounds of lunar rock and soil were brought back to Earth for analysis. Lunar rocks, composed of minerals like basalt, anorthosite and breccia, are formed in a unique environment without wind or flowing water. These rocks have been on the moon’s surface for a long time, accumulating valuable information about its geological history.

Check out the out-of-this-world activity below to explore the chemistry and composition of your own imitation lunar rocks!

Materials Needed:

• Baking soda (4 cups)
• Bowl
• Cookie sheet
• Dropper or squeeze bottle (optional)
• Paper plate
• Pencil
• Scrap paper
• Spoon
• Vinegar
• Water (1/4 cup)

Step-by-Step Instructions:

1. Using a spoon, mix baking soda and water in a bowl.
    
2. With your hands, pick up pieces of the mixture and roll them into small “lunar rocks.” You can try making rocks of different shapes and sizes.
    
3. Place your rocks on a cookie sheet and let dry overnight.
    
4. Fill a squeeze bottle or dropper with vinegar. You also can use a spoon in place of a bottle or dropper.
    
5. Once your rocks have hardened and are dry, place one rock on a paper plate.
    
6. Place a few drops of vinegar on the lunar rock.
    
7. Write down your observations.
    
8. Repeat steps 5-7 until all your rocks have been dissolved.
    
9. Share your observations with friends or family.

What Are We Discovering?

When you dropped vinegar onto your “lunar rocks” made of baking soda, you observed a chemical reaction. When combined, these ingredients reacted, producing the gas carbon dioxide, which caused the “lunar rocks” to bubble.

This is similar to how scientists might use chemical reactions to figure out the composition of rocks. National Inventors Hall of Fame^® Inductee George Alcorn invented an X-ray spectrometer, which is an incredibly useful tool that allows scientists to identify what materials planets and moons are made of without the need for human missions. It also helps them search for new planets in other solar systems. By studying lunar rocks, we learn more about the moon and its history. The rocks can tell us how old the moon is, what it’s made of and how it was formed.

Much of what is known about space results from the vision, creativity and innovation of National Inventors Hall of Fame Inductees. Robert Hutchings Goddard invented the rocket power that made lunar exploration possible, Maxime Faget invented the space capsule that carried astronauts to the moon and back home safely, and George R. Carruthers invented the camera left on its surface to study the Earth’s atmosphere.

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