A DIY Planetarium

Introduction

Back in the early 80's my local astronomical society had grand plans for a observatory and planatarium, however nobody would give us the vast amount of money needed for such buildings. It was then suggested to me that a portable planatarium would be a good idea, but how was it to be built. Long before the advent of the Home Planetarium Association, I had very little outside guidance. To project the stars the pin-hole method seemed the cheapest, (at the time I had just left school, and money was short), but how was the dome to be constructed. Fortunately another very keen member suggested a geodesic frame-work.

The stage was set, but deciding what to use for the 'star-ball' and how to build the dome caused alot of head-scratching.

The Star-ball

This was the easiest part, given the available bulb the minimum size of star-ball was though to be 2ft (60cm), even then the brighter stars (requiring larger holes) would need lens to focus the light beam, to avoid loads of full-moon's over the sky. To follow the story further, with pictures click here

The Dome

It had to be big, I wanted to fit in all our society members, then in the 20's or a typical class of school kids. So sizes of 15-20ft (5-6m) where talked about. I had seen pictures of the geodesic domes like I wanted to build, but how was such a thing put together, all became clear after a friend showed me a copy of The Dome Builders Handbook a wonderful American book, in which people showed how they had built their dream-dome, and lived in it. Well my dome would not have to be that sturdy, but the plans where there, more details to follow... (page under construction)

Other DIY'ers

There now exists the Home Planetaruim Association devoted to like-minded persons.

Email Gary for more details.

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