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 "MS" line was built by Minolta from 1960 to 1985. These dumbbell projectors exhibit various quality levels - the easy ones are school devices with 2500 star spots through precise projectors with 9000 stars for large domes. The model updates are chronologically numbered. MS-10 was the first projector sold to Europe. It was set up in Tampere, Finland, in 1969, but destroyed three years later because of a major fire. Later, it was substituted by a MS-15 (image). This version was permanently improved and reached a summit by being Minolta's most successful projector in the USA. It is customised to 14- to 17-meter domes. The first fully automated system was MS-18 presented in September 1978 in Tokyo. The series ended with MS-20 in 1980. The US company Viewlex sold the machines also under its own name.

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.

1774: The largest orrery still in use was built the Dutch Eise Eisinga (1744-1828) into the ceiling of his living room in Franeker. The gearing mechanism is driven by several pendulums and weights that steer an impressive wheel work hidden behind a wall. The wheels are made of wooden tyres and disks, and the cogs are actually nails. The planets run in visible circular rails. Their periods around the sun correspond to the real times, i.e. Saturn needs 29.5 years for a complete turn. Thus, the momentary positions can be read off at any time. The planetary orbits are divided in accord to the zodiac showing their positions within the constellation figures in the sky.

Pre-recorded planetarium shows are often associated with music, interludes and presentation of pictures. The planetarium acts like an artist or broadcaster, so, a public performance is due to copyright laws, unless the facility itself is the composer, producer or publisher. Buying a CD from a music store confers the rights for private use, but not for public places like theaters, shopping malls, radio stations -- and planetaria. This commercial use of the music as well as pictures demands payment (royalty) to the copyright owner. That permission can be obtained on two different ways: either directly from the copyright owner (composer, publisher), or from a "performance rights organisation". The latter acts as an intermediary between a collective of many copyright holders and those who wish to use the copyrighted works (customers). As such, it manages simultaneously a great repertoire of songs, and keeps negotiations with the rights holders. The licence details differ due to national laws, however, there is at least one performance rights organisation in each country.