This online encyclopedia is a large sample of comprehensive data offering you a possibility to find any information about planetariums. You are given lots of information about space theaters, projection techniques, history, and new developments. Dates of general interest like international conferences and meetings are updated as soon as announced. Our objective is to point out the important role that planetaria play when bringing astronomical knowledge from the scientific frontiers to the public. On these pages you will find inspiration for new projects that may help you to attract visitors and guide them through the fascinating sites of our Universe. If you still miss anything, don't hesitate to contact us.

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The realisation of the modern planetarium comes in many shapes and sizes, ranging from a small umbrella-like facility of hardly 3 meters to huge domes providing space for several hundred visitors. Such a planetarium may shelter an opto-mechanical star projector (the classical style) as well as a number of video projectors for a digital presentation (virtual style). Difficulties arise when evaluating a planetarium's prominence, especially, when seen through the eyes of the public, who are accustomed to classifying them to "large", "middle", and "small" buildings. A closer look at the parameters, that determine a planetarium, reveals that only two are stable against arbitrariness: the diameter of the dome and the type of the projector. The number of seats, often mentioned in the planetarium's description, turns out to be of little significance.

1958: The leading Japanese industrialist Seizo Goto, who established his company to produce telescopes in 1926, expanded to include projectors for planetaria. Only a little later, the Minolta Company got into the same act and presented its first projector "Model #1" (image) at the Science Exhibition in Hanshin Park in Koshien (close to Kobe). It was not until the end of the 1960ies, when the company decided to continue this branch and improve the technics. The next steps forward came with the MS-series. A full automation system based on a microcomputer was developed in 1978 and integrated into the model MS-18.

Astronomy is one of the oldest of the natural sciences, and it is said to be the "noblest". A quite young and related field is space science that explores the technical abilities to bring us closer to the Cosmos. Children are impressed by both branches, when they develop their own identity and get confronted with the view of the world. Astronomy offers a starting point for many other topics in natural sciences. While the planetarium fascinates with the starry sky and show effects, a science center puts the basic scientific phenomena into practice. The combination of a Planetarium and a Science Center is close at hand. Different to a classical museum, the Science Center does not present original exhibits, but commodities to be utilised for experiments. The learning effect focuses on the personal confrontation with the phenomenon. From the didactical point of view, this direct experience of science leaves behind a sustained knowledge of the technical processes.

The expression IMAX descends from the expression "images maximum" and denotes a very large film format. It was developed by a Canadian company for huge screens to make the spectators feel as being part of the scenery. Different from the "usual" cinematic movies, this technique uses very much larger picture formats, high-powered projectors with Xenon-bulbs, and horizontal transportation of the film reel. Several other mechanisms care for a brilliant, sharp and flickerless image. Due to technical and economical constraints, most of the produced movies have a scientific content. Several variants of IMAX theaters have been developed to bring the adventure closer to the visitors. In particular, planetaria use the system "IMAX Dome" (formerly called "Omimax"). Here, the projector is located close to the geometrical centre of the building instead of the rear projection. Since the screen is curved, a lot of special features about the camera, the lenses as well as the projecting devices have to be considered. Most of all: Distortions to the edge must be corrected. The seats in the IMAX Domes are unidirectional and tilted (most often: 20°). As such, only one half of the hemispheric dome is deployed, but not the full hemisphere as a planetarium with concentric seats would do.