How to Make a Cloud Chamber




Introduction: How to Make a Cloud Chamber

In this brief tutorial we will show you how to build a cloud chamber with a brief explanation of how it works and images to refer to when in the process of making.

But, what is a Cloud Chamber?

A cloud chamber is a simple contraption that lets you see muons, an elementary particle similar to an electron, passing through a cloud of alcohol.

Step 1: Acquire Your Materials

Before you start with the construction of a cloud chamber, you first need to acquire required materials.

Note that a radiation source is optional as we will be using cosmic rays for this.

Here is a list of what is needed:

  • Dry Ice
  • Safety gloves ( For handling the dry ice; best if cryo gloves)
  • Styrofoam container ( For holding the dry ice )
  • Black clay
  • Rubbing alcohol ( You will want to have the rubbing alcohol at around 99% in concentration. To do this, you can follow this tutorial: )
  • Plastic cup
  • Felt ( Black for best visual )
  • Metal pan


  • Radiation source ( rather than just relying on cosmic rays, you can place a radiation source in the chamber to see the emission of other particles )

Step 2: The Felt

Take the plastic cup and line the bottom inside area with felt.

Step 3: The Clay

Next, line the inside of the cup and rim with clay.

The clay on the inside will help hold the felt to the inside of the cup and the clay on the outside will later be used to create a seal.

Step 4: Safety Equipment

Now, put on your cryo gloves and fill the metal dish with dry ice.

Dry ice is around -110 F or -78.5 C. So needless to say, it's a just a tad bit cold. You definitely do not want to come into skin contact with it.

Step 5: The Dry Ice

Once pan is filled, place styrofoam lid on top of pan. Proceed to flip both pan and styrofoam together.

Step 6: Preparing the Cup

Now, soak the felt with the rubbing alcohol and place the cup upside down on the metal surface containing the dry ice.

It's important not to place too much alcohol in the cup. You want the felt to be saturated but not to the point where there is a noticeable amount of alcohol inside the cup.

Step 7: Watch for Trails

Now that the felt is soaked in rubbing alcohol and the dry ice is underneath it, you now have to wait about ten minutes for the alcohol to form a cloud inside the cup.

Once it has done so, you should be able to see little trails in the clouds. This is best seen in a dark environment with a flashlight.

Be the First to Share


    • Block Code Contest

      Block Code Contest
    • Baking Contest

      Baking Contest
    • Game Design: Student Design Challenge

      Game Design: Student Design Challenge



    5 years ago

    Would regular Ice work for this??? Or snow?


    7 years ago

    Now introduce fire or a spark gap inside of the cup


    Reply 7 years ago

    Wouldn't the co2 from the dry ice put fire out?


    This is an awesome project! I remember doing it in Elementary school. Awesome job!