First demonstrated in 1923, a planetarium is a device that projects dots of light onto the inside of a dome to simulate the night sky. This article outlines how to use inexpensive materials to make a simple tin can pinhole planetarium that can be used to project the stars of a single constellation onto a flat surface such as a wall. Alternatively, you can simply look into the tin can and see the constellation pattern.
Making this pinhole planetarium will also help children in the Scouting movement earn their astronomy badge.
- Clean tin can with both ends cut off
- Scissors, sticky tape, aluminium foil, rubber band, needle
- Optional: Torch
- Constellation pinhole planetarium disc:
- Scorpion (Scorpius) pinhole planetarium constellation disc (Adobe Acrobat format)
- Southern Cross (Crux) pinhole planetarium constellation disc (Adobe Acrobat format)
- Avoid cutting your fingers on the tin can edges.
- Use caution when making the star holes with sharp metal instruments such as needles.
- Do not look through the pinholes at the Sun.
Step 1: Cover sharp edges of tin with sticky tape.