How to Make a Telescope at Home

Making a telescope at home is a fun, simple activity which requires very few materials. A basic refracting telescope can be made using two lenses and two sturdy cardboard tubes. Of course, you can tweak your telescope by using a concave lens for the eyepiece, so the image won't be upside down, and by making the tubes out of a stronger material than cardboard. The telescope will work the same no matter what materials you use.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• 1 small eyepiece lens
• 1 large objective lens
• 2 sturdy cardboard tubes
• Scissors
• Duct tape

1. Gather your materials. The basic materials you will need for your telescope are two lenses -- a bigger lens, which is your objective lens, and a smaller lens, which is your eyepiece. You also will need two cardboard tubes to hold the lenses. One tube should be just a little wider than the other tube so that the smaller tube can slide in and out of the larger tube.

2. Focus the two lenses to see how they work. Place the small lens near your eye and take the larger lens and move it backwards and forwards. The image will appear blurry until at one point, everything will come into focus. This is how your telescope will work.

3. Mount one lens on each tube. Take the bigger tube and cut a slot for the objective lens and slide the lens in. If you need to, build a gasket out of Styrofoam to help hold the lens in place. Secure the lens using duct tape. Then do the same for the eyepiece lens.

4. Insert the smaller tube into the bigger tube and focus the telescope. To focus the two lenses, simply look through the smaller lens and focus the bigger lens on an object. Then move the smaller tube back and forth inside the bigger tube, until the image you are focusing on comes becomes sharp.