Some meteorites have enough energy and mass that when they hit the Earth, they make a large circular indention in the surface called an impact crater. Impact craters can take on various shapes based on the meteorites' size and the speed they hit the Earth. Try this activity to learn more about meteorites and impact craters.
What You Need:
- About 3-5 small round rocks and/or balls of different sizes, about 1/2" to 2-1/2" in diameter
- Plastic tub
- Cocoa powder
- Flour sifter or salt shaker
- Meter stick or measuring tape
What You Do:
- Spread the newspaper on the floor and place the plastic tub in the center.
- Fill the tub with flour so that it is about 1-2 inches deep. Don't compact the flour by pressing on it.
- Using a flour sifter or salt shaker, sprinkle an even layer of cocoa powder over the flour.
- Select your first rock to be a meteorite.
- Using the meter stick, select a height to drop the rock from and then drop the rock into the pan at this height. Carefully remove the rock from the flour. Observe the crater it made (the cocoa powder will help you see how the surface moved).
- Without fixing the surface of the flour, select another rock to drop into the flour. Drop it from the same height as you did with the previous rock (but drop it away from the first crater). Compare its crater with the first crater.
- Continue dropping the rest of your rocks at the same height using the same flour surface. Drop them so that they each make their own separate crater and don't overlap. Observe and compare each of the craters.
You are simulating what happens to the Earth's surface when large meteorites hit the surface - the formation of impact craters. From this experiment, you should notice that the size and mass of each meteorite changes the size and shape of each crater formed. The cocoa powder represents the very top layer of the Earth and shows how debris is ejected during the formation of the impact crater, also known as ejecta.
To extend this experiment, try dropping the same rock from varying heights onto the same bed of flour. Try changing the depth of the flour or try compacting the flour. On each of these experiments, observe and compare the craters formed by the meteorite impact. You may even want to try having someone else drop a "meteorite" into the flour. Then, based on the size and shape of the crater, guess as to which meteorite hit it and at what height.
Earth is not the only body in the solar system that gets struck by meteorites. The planets and moons all get hit by them as well. Here is an image list of some of the more famous craters found on our Earth and throughout the solar system.