Try This: Make Cocoa Craters
This #SMOatHome is part of Space Day presented by Allied Arts!
When a meteorite is very large and very fast, it may have enough energy to make its way through the atmosphere and strike the surface of the earth. These space rocks can be moving at tens of thousands miles per hour. They have enough energy to vaporize solid rock and send it hurling back into space!
Fortunately, meteorites that large are rare. Most meteorites are small. These break apart and burn up, as they’re heated by friction from the atmosphere. They make bright streaks, that we often call “shooting starts” before eventually falling to the earth as dust.
On the Moon, with no atmosphere, craters are formed by even the smallest meteorite. And with no erosion, they stay where they are unchanged, until another meteorite forms a crater on top of them.
In this activity you’ll see how craters are made, and more specifically, how rocks from deep with the Earth get moved to the surface when a crater is made!
Here’s what you need:
- Baking pan
*If you plan ahead and research some recipes before you start, you can use the correct amount of flour and cocoa to allow you to recycle the craters into a treat like brownies or chocolate cookies!
Here’s what to do:
You may want to do this activity someplace where you can make a small mess, because the cocoa and flour go farther the faster the marble travels, and you’ll want to have some fast impacts.
1. Pour flour into the bottom of a pan and spread it into a smooth layer that is about an inch thick.
2. Use a sifter to sprinkle a thin layer of cocoa on top of the flour.
3. Drop a marble into the cocoa and flour to make a crater.
4. Try dropping the marble from different heights or different angles to see if the craters look any different.
What is happening:
The flour represents the core of the planet. The cocoa serves as the crust. The marble represents the meteorite, which is also called the impactor if it reaches the surface. On planets and naturally satellites, the crust is generally a rocky shell instead of fine powder like cocoa. The energy of impactors that form craters are still great enough to vaporize the crust and core beneath it, sending it flying outward just like this fine powder. Material sent out of the crater by the impact is called ejecta. You may observe this in one of the craters that you made that has brought a lot of the flour to the surface. On Earth we find rare minerals from deep within the planet around and within craters, such as the gold and diamond mines in South Africa around the Vredefort crater.