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archive:science:humble.how
                    THE HUMBLE TELESCOPE
                         David Daye
                        Columbus, OH
   A quick, fun telescope project for kids and lazy adults is the

Humble Telescope, a solar viewer that can produce foot- to yard- sized images of the sun, including sunspots down to a few earth diameters. And although far simpler than a similarly-named instrument, the Humble Telescope may be a more reliable, cost- effective way of viewing of detail on a heavenly body.

   Since a pinhole camera works not by refraction but by simple

geometry, it follows that a tiny MIRROR should create as good an image as a pinhole in a lightproof box. The advantage of the mirror is that you can shoot its image anywhere you please, into a darkened room far enough back to produce big if somewhat dim images. You can only do that with a pinhole by making a barn-sized viewer.

   As with the Other telescope, the key element here is a special

mirror – but this one only needs to be a flat FRONT-silvered one, in almost any shape of 1 square inch or more. While you, too, can have one specially made by a government contractor, you can also pick one up in any shopping mall parking lot, where they are produced by the timeless forces of automobile fender-benders.

   The shiny part has to be on top, because the image is ruined

if light has to pass in and out of glass. Clamp the mirror to your camera tripod (kids: stick it on a dry rock with bubble gum). Now make the pinhole "mask" that does the actual imaging. Take your business card (the gum wrapper) and poke a 1/8" to 1/4" hole with your executive pen (rusty nail).

   Open the window of your viewing room--glass, screen and all--

and block off most of the opening with shades or towels. Go out into the sun and use the light of the full mirror to aim the image into the room. (Prop your mounting rock into position.) Gently tack the mask over the mirror with tape so that only the pinhole area is exposed.

   Dash in and watch or photograph at will!  Sunspots appear as

dim smudges that wiggle and move along with the image of the disk. You have about a minute before the disk tracks away from the window. The farther the mirror from the wall, the bigger but dimmer the image. The bigger the pinhole, the brighter but blurrier the image.

   For better viewing:  1) Set up a flat, white cardboard or

screen for the image. 2) Keep the room the same temperature as outoors to minimize heat distortion. 3) Keep the room dark as possible so as to see more dim sunspots. 4) Have parent or teacher do the aiming so you can keep your eyes used to the dark.

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