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Planetarium

The geodesic dome of the Planetarium in St. Petersburg is part of a large-scale idea to transform an industrial area into both a modern architectural project and a scientific and educational centre comprising of "the world’s largest planetarium."

The dome was built in 1884 by Rudolf Bernhard for the 'City Lighting Society' of St. Petersburg. It is located on a water canal, and is an architectural monument with historical significance. Originally used for storage space and to supply gas to street lamps,it has remained abandoned for 120 years — since the appearance of electricity. In 2015, the person behind the now-existing Planetarium saw the old gas-holder dome for the first time, and a thought about a large planetarium inscribed into the existing architectural design came to his mind. Two years later, this dream, seemingly fleeting and incredible at the time, came true — the planetarium was opened in November 2017.

The historical evolution of the architectural dome was marked by the appearance of a geodesic dome inside the Schwedler dome. As the next stage in the development of these structures, the geodesic dome was based on a more optimal (in terms of structure) geometric model of construction. It is noteworthy that the first full-sized geodesic dome (based on the icosahedron) also was a planetarium, opened in Jena in 1926.

The old gas-holder dome is a brick tower of 42m in diameter and 20m in height, with a total volume of 40,000 cubic metres. On the top of the building one finds a Schwedler dome with radial metal trusses, connected by rods that form a self-stressed "bicycle wheel" structure. Constructions such as this geodesic dome laid the foundation for the development of lightweight, load-bearing structures that covered large-diameter spaces.

The task of constructing a three-dimensional projection screen in a half-sphere of 37m in diameter dictacted in large part the theme of the place. Ten frequency spheres influenced the choice of material for its parts, which is foamed PVC. The structure is composed of the hexagonal grid, or fullerene. Thus, in each triangle of the geodesic dome framework, a hexagonal element is present. The elements form a single screen, which consists of 1400 parts of 36 dimension types.

 

Architects | Geosota, St. Petersburg, Russia

Location | St. Petersburg, Russia

Technical Information | PVC foamed panels

Picture credits | Anastasia Ra, Daria Priroda, Olga Romanenko