Asteroid Impact Demo
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1. Objective:

To learn how the craters on the Moon came
to be, and how their appearance depends
on the nature of the impacting object.


2. Prep Work:

Show an image of the Moon and discuss
the appearance of various craters.


3. Equipment (for each group):

1 aluminum baking pan 4-5 inches deep (Walmart, $1-2)
2 pounds flour
1/2 cup cocoa powder
1 small sieve (to distribute the cocoa powder)
10-20 "asteroids" (beads, nuts, stones, small compact household odds and ends)
1 ruler


4. Instructions

Take the baking pan and fill it with flour 
3-4 inches deep. Then add a thin layer of 
cocoa powder over the flour.

Now take some "asteroids" and throw them into
the pan. 

You will see a crater, and you will see white
flour sprayed into various directions (rayed 
ejecta). Compare this to the craters you see 
in the image of the moon.

Try altering the size and mass of the asteroids, 
as well as the angle of impact.

See how the size and depth of the craters and 
size/directions of the ejecta change.


5. Assessment

I first show the image of the moon and point
out the craters. I asked what made the craters.
Afterwards I ask them to compare the appearance
of the pan to the moon image and describe what
they see. I am looking for parallels in appearance
of the craters. 

A followup is to ask them what happens if you
alter the size and mass of the asteroid, as well 
as the angle of impact.

6. Origin of this little demo? 

This was demonstrated by Tim and Stephanie
Slater during teacher workshops on the Big
Island of Hawaii.