Creating Moon craters

Credit: NASA

If you've ever seen a photo of Earth's Moon, you may have noticed that there are numerous craters on its surface. Some of them are bigger than cities on Earth! About 80% of the Moon's surface is covered in craters. These are impact marks left on the Moon's surface by ancient meteorites or other celestial bodies. Meteorite impacts have been shaping Earth and the Moon for over 4 billion years. Craters on the Moon are virtually permanent, as opposed to those on Earth. Earth has processes such as erosion, which constantly changes Earth's landscape. As a result, traces of craters are harder to find.

In this activity, you will be recreating the Moon's craters and exploring how a crater's size, ejecta, and characteristics depend on the incoming meteorite's mass, velocity, angle and height. The Moon's Tycho crater (bottom left), which looks like the navel on an orange, is 86 km in diameter, almost 5 km deep and approximately 108 million years old.

Did you know?

You will need:

How to make your craters:

  1. Lay down several sheets of newspaper for easy cleanup.
  2. Pour and evenly spread 5 cm of flour in your baking tray or plastic container.
  3. Using the sifter, evenly sift 1 cm of cinnamon or cocoa on top of the flour. This will be the Moon's surface.
  4. Hold your first rock 40 cm to 50 cm above the tray or container.
  5. Drop it into the tray or container to simulate a meteorite impact.
  6. Carefully remove the rock and observe the crater created. The material that was ejected is called the ejecta.
  7. Experiment by dropping differently sized rocks at various angles and heights, and see how one ejecta pattern differs from the next.

Earthrise as captured by the crew of Apollo 8 on . It was the first manned mission to enter lunar orbit. (Credit: NASA)

How it works:

When you throw a rock, it gains kinetic energy (which means the energy that an object has because it is in motion). When the rock hits the flat, powdery surface, its kinetic energy is transferred to the powder and creates an impact crater. Try different heights (e.g. 1 metre, 2 metres) and different angles. The craters should change their shape depending on the speed, size and angle of the incoming meteorite. Higher-energy impacts make bigger craters, with debris shooting out from their centres as "rays." Throwing a rock at an angle makes an oblong crater.

Calculate the effects of a meteorite impact on the Moon, Earth and Mars using the Impact Calculator.

Terminology:

Date modified: