Pretty much everyone knows what a telescope is and what it does. What not a lot of peeps are aware of is how a telescope actually works. They’re not actually as complex as one might think, as this handy dandy Demo Science science demo will show.
So gather your students (or whoever) around and show ‘em how to tele their own scope.
Exacting & Refracting
In this experiment, you’ll be creating a simple refracting telescope with just a few items. You’ll need a sheet of notebook paper or tagboard (which tends to work better, as it’s stronger and more durable), two magnifying glasses, and something far away to look at—if you’ve got a window to look out of, you’ll surely be able to find something outside to espy.
The first step is to darken the room, so either shoot all the lightbulbs with a pellet gun or just flip the light switch off. Close your non-dominant eye and look out the window through one of your magnifying glasses. Move the lens back and/or forth in front of your eye until you can see whatever it is you’ve chosen to look at through the window in clear focus.
Without moving the lens, hold up your paper or tagboard between yourself and the lens. You may need to round up an assistant for this part, so make sure you call on one of the less spazzy students. Hand the paper off to little Tayden or Kadence or Flamingo or whatever undoubtedly stupidly-named kid you’ve enlisted and have them move it back and/or forth until a clear image appears on the paper. Whatever you were looking at outside will appear small and upside down on the paper.
Take the paper from the little rugrat and have him or her sit back down and pay attention. Replace the paper with the second magnifying glass, and adjust its distance back/forth until you’ve got a clear, non-blurry image showing through both lenses. Get a different smelly kid to hold up the paper or tagboard this time and repeat your adjustments until a larger, clear, less upside down image appears. You’ve just created an exceptionally basic telescope.
It’s Science, See?
This demonstration simulates the workings of a refracting telescope. The first magnifying glass represent the objective lens, which is intended to capture light from distant objects and bring them into focus. The paper/tagboard is the focal point where the clear image exists. The second magnifying glass is, essentially, the eyepiece lens of your telescope. This lens collects the light from the focused image at the focal point and enlarges and inverts it for proper viewing.
Be sure to give credit to Alphonse Rudolf Telescope, inventor of the telescope.