A Backyard Dome Observatory

The observatory dome is constructed of polystyrene "bead-board"
coated with a thin layer of reinforced concrete "stucco".
The design is a simple geodesic dome ala Buckminster Fuller.
As constructed the building is 9-1/2 feet in diameter.

Footing and Telescope Base

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The building footing and the telescope base are of poured concrete. The two foundations are separated as far as possible. The building foundation is a ring of the appropriate size placed just deep enough to be below the frost line. The telescope base is much deeper. The base rests on very firm soil (preferably bedrock). The telescope base is isolated from the building foundation and the observatory floor to prevent vibrations being transmitted to the telescope.

Floor and Walls

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The building wall is framed with 2x4s. The exterior of the wall is covered with colored roofing metal. Floor joists are 2x8s on 16 inch centers. The floor is 5/8 inch plywood. The bottom plate is cut from pressure treated 2x6. The top plate is a double circle of 2x6. The floor is 18 inches below the top plate. This gives plenty of head height to the dome for a person 6 feet tall.

Dome

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The dome design is a common geodesic dome. It is a combination of pentagons and hexagons. Each pentagon is surrounded by 5 hexagons. The dome is slightly greater than a hemisphere. The dome requires 6 pentagons, 10 hexagons and 5 half hexagons. As constructed, the sides of the polygons are 2 feet. This gives a dome diameter of 9-1/2 feet. It also matches the size of the foam board, available in 4x8 feet sheets.

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To view the stereo-pair of the observatory, move back from your screen 4 - 5 feet, cross your eyes to register the two images; concentrate on the center image.

Go to Construction Detail Page

Other Builder's Comments/suggestions

Check out these [not all] foam dome projects:
A.S.I.G.N. Observatory Canberra, A.C.T.
Steve's dome in Queensland Australia
Here is another, this one is Steve's (from California)
Clement Svensson of Sweden has a new dome
Neville Fraser of New South Wales in Australia also has a foam dome
Andy's Dome In Apache Junction AZ
Here is a dome from "down-under" made of plywood, looks like a good idea for those who like woodworking
Barry Neumann, also from "down-under" made his dome using fiberglassed cardboard

Questions / Comments contact: jgarlitz@orednet.org
Joe Garlitz Index Page

CCD Images:

CookBook245 Images from Elgin

Telescope and Control Hardware

Remote Focuser Project

Designing an A-Thermal Optical Tube Assembly

Where in the World is Elgin
45 deg - 34 min - 22sec : 117 deg W - 55 min - 16 sec