Day 2 – Build your own telescope
What is a telescope?
A telescope is a tool used to look at distant places as if they were nearby. While telescopes have countless different brands and manufacturers, the mechanics behind every telescope is the same. A telescope is used to gather light using either mirrors, lenses or a combination of both. The light gathered is then sent down the length of a tube into the eyepiece which is where we see the image.
For children who have begun to shown a growing interest in the planets and the stars, you may want to try out this simple DIY telescope before investing in something larger and more expensive only to have them lose interest in a few days. If they truly do enjoy astronomy, get them something with higher quality and functionality then! But before we get to the experiment, let’s briefly identify and talk about the most important parts of the telescopes. Without these parts, the telescope would not be able to do its job.
Parts of the Telescope
The Eyepiece – what you will be looking through. The eyepiece is among one of the important factors that determines the magnification (how big the image) you will see. Generally, the smaller the eyepiece, the larger the magnification.
The Optical Tube – Light travels down this tube from the objective lens to the eyepiece. Generally, the longer the optical tube, the light travels a further distance and results in a higher magnification.
The Objective Lens – Where the light enters and is gathered by the telescope. The size of the objective lens refers to the diameter of the lens in millimetres (mm) or inches (in). Usually, the wider the objective lens, the brighter the images.
The Tripod/Mount – What the telescope rests upon for stability and orientation. Mounts can have other features that will make telescopes easier to use and more enjoyable, for example it can have a GO-TO system in which the telescope can orientate itself towards a desired celestial or planetary object.
Now that we know the parts of the telescope, you are better equipped to try out the simple activity below. Today, we will be outlining how to make a simple telescope. It is best done with the adult taking care of the cutting and the child doing the decorating due to the presence of sharp lenses and the use of scissors and blades.
Simple DIY Telescope
Materials
- Two convex glass lenses* – one small**, one large.
- One long cardboard tube (must be wider than the lenses)
- Two large sheets of cardboard
- Stanley Knife
- Scissors
- Plastic tape
- Super glue
- Pencil
*Convex glass lenses can be found online or at your local educational science stores.
**Generic sizes were stated as every store sells lenses with different specifications. Please purchase accordingly!
Instructions
- While resting the flat end of the cardboard tube on the large cardboard sheet, trace around its circumference.
- Turn the cardboard tube around and repeat on the other large sheet of cardboard.
- Using scissors, cut around the outlines you have just traced on both sheets of cardboard, leaving you with two circles.
- Carefully, trace the edge of the small convex lens on one of the cardboard circles you have just cut out and trace the edge of the large convex lens on the other.
- Using a stanley knife, carefully cut out the inner proportion of the circle (ie. the inside part of the circle you have just traced) of both cardboard circles.
- Line the edges of the lenses with super glue and paste it to the circular cutouts corresponding to the size of the lenses.
- Leave for 15 minutes or more in a steady position for the glue to harden, or according to your glue’s directions.
- Tape over the glue while leave the lenses clear to ensure that the glued surface is smooth. It also provides an extra layer of support to keep the lenses attached to the cardboard cutout.
- Coat the flat edge of the cardboard tube with super glue and attach the cardboard circles with the lenses onto each side. The smaller lens side becomes your eyepiece whereas the side with the larger lens because your objective lens.
- Leave for 15 minutes or more until the glue reaches its maximum strength.
- Secure the edges of the tube with tape.
- Decorate as you wish! Use glitter, markers, stickers, and more.
If you do happen to make a telescope, we would absolutely love to see it. Please send us a picture of your creation.
If you have any questions about what you have learned today, please feel free to contact us at support@opticscentral.com.au or leave a comment down below! We would love to hear from you.
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