Pinhole Sun Viewer

With your very own pinhole sun viewer you can safely observe, sunspots, eclipses, and other solar phenomenon from anywhere the sun is shining. The pinhole narrows the amount of light rays that can enter into the viewer, and causes a similar effect as a converging lens does. What you get is an inverted image of the Sun. If you were to view a solar eclipse with a pinhole viewer, you would see a dark circle slowly move across the sun. Something that occurs more frequently is sunspots. You would notice areas of the Sun’s image would appear to be darker than other surrounding areas. With paper you could trace where these sunspots appear in the image and be able to determine where a strong magnetic field is occurring on the Sun. The Pinhole Sun Viewer is an easy tool to make and only requires a few items that you can find at home! 

Materials

  • Cardboard box, like a shoebox or soda can box
  • Tin foil
  • Tape 
  • A thing gauge needle 
  • Exacto Knife

Steps

  1. Cut a 2 cm x 2 cm square in the center of the end panel of the box
  2. Cut a 3 cm x 1 cm slit lengthwise on one of the longer side panels of the box approximately 2-3 cm from the end of the box farthest from the first square hole. This will be your viewer. 
  3. Cut a 3 cm x 3 cm of tin foil and place it so it’s covering the 2 cm x 2 cm hole on your box, then tape the edges of the foil to the box. 
  4. Using your thin gauge needle carefully poke a pinhole through the center of the tin foil making it as round, uniform and small as possible. 
  5. Tape or glue a piece of paper on the inside of the box opposite of the pinhole to make a viewing screen. 
  6. Orient the pinhole inline with the sun. You can use the shadow of the box on the ground to help you focus your image by aligning your box in a way where you make the shadow as small as possible so you don’t see the shadow of any of the side panels of the box.  
  7. Look through the viewing slit on the side of the box and you should see an image of the Sun right on the end of the box opposite of the pinhole.