In 1874, a book featuring photographs of plaster of paris models of the moon was released. The images turned out so real, many wondered if they were taken on the moon. Now you can make your own 3D model of a lunar crater.
First find a picture online of a crater that you want to make. The craters Tycho, Kepler, or Copernicus work well. Print two enlargements of the crater on letter-size paper. Cut one out and, using the black felt marker, trace it directly onto the foam board. Now we know how big our crater is going to be. The other printout will be our guide for adding details.
Prepare your plaster of paris mixture: Pour half a cup of cold water into your empty mixing container. Take 2 large spoonfuls of dry plaster of paris and gently sprinkle them into the water. Stir the mixture around, and add a bit more plaster or water until it has the thickness of milk.
Tear off little pieces of paper towel about 2 inches wide by 5 inches long. One at a time, dip them into the plaster and arrange them around the outline of the crater, squishing and shaping them with your fingers. Keep adding more plaster-soaked paper until the rim of the crater is complete. Work quickly because the plaster will set in about 6 to 10 minutes. Any plaster that drips onto the foam board can be smeared around using your fingers.
While waiting for your rim to harden, scrape out any extra plaster in the mixing container onto a newspaper and toss it into the trash. Rinse the mixing container in the bucket of water. Apply masking tape all around the outside edges of the foam board to keep plaster from running off the edges onto your surface.
Mix another full container of plaster.
Build the crater walls higher by dripping on spoonfuls of plaster, and spread some on the crater floor. Pour the new container of plaster around the outside of the crater to make the lunar surface higher. You may need to add another container of plaster later if the lunar surface is not high enough. Drip a little bit of plaster in the middle of the crater to make tiny peaks and wet the end of the pencil eraser and twist it around the drying plaster to make nice little craters. Use the sharp end of the pencil to trace in little cracks on the crater floor. Add more little craters as needed.
Clean out your mixing container once again, and set your crater aside in a warm room to let it dry overnight.
In your clean mixing cup, pour in about a 1/2-inch layer of white glue and add about 1/2 inch of cold water to thin out the glue. Dip your paintbrush in the diluted glue and quickly paint over your entire plaster model with a layer of the glue.
Quickly sprinkle on the grout or cement mix until everything is covered. Now, once again, wait until everything dries. Then pick up the foam board and walk outside to gently blow off any loose dust.
You’ve just made your own model of a lunar crater! If you want to get really crafty, put your model in a darkened room and shine a light on it from one direction, just as the sun would be shining on the moon. With a cell phone, take a picture of it. It’ll look like you shot a close-up image of the moon through a big telescope.
DRAWING THE MOON
For centuries, the only way to record surface features on the moon was by making drawings. To become a genuine lunar artist, head outside to get started sketching.
Place the round object in the middle of your paper and trace around it with your pencil. That’s the outline of the moon that you’re now going to fill in.
The first thing to draw in is the terminator line. Remember, that’s the dividing line between night and day on the moon. Everything you draw in will be on the daytime side.
Look through your telescope and lightly sketch everything you see on the daytime side of the terminator.
When you’re done, go back inside and make the lines darker and shadow in the nighttime area. In the upper left corner of the paper, be sure to write the date of your drawing, the time of night, and the power of the eyepiece you used on your telescope. Go outside on several nights and make a drawing each night. You’ll be amazed at how lunar features change over time.
REPRINTED WITH PERMISSION FROM THE NAT GEO KIDS BOOK LUNA: THE SCIENCE AND STORIES OF OUR MOON, COPYRIGHT © 2019 NATIONAL GEOGRAPHIC PARTNERS. ALL RIGHTS RESERVED.