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73-555: Eretz Israel Museum, established in 1953, has a large display of archaeological, anthropological and historical artifacts organized in a series of exhibition pavilions on its grounds. Each pavilion is dedicated to a different subject: glassware, ceramics, coins, copper and more. The museum also has a planetarium . The "Man and His Work" wing features live demonstrations of ancient methods of weaving, jewelry and pottery making, grain grinding and bread baking. Tel Qasile , an excavation in which 12 distinct layers of culture have been uncovered,

146-478: A star ball , slide projector , video , fulldome projector systems, and lasers. Typical systems can be set to simulate the sky at any point in time, past or present, and often to depict the night sky as it would appear from any point of latitude on Earth. Planetaria range in size from the 37 meter dome in St. Petersburg, Russia (called "Planetarium No 1") to three-meter inflatable portable domes where attendees sit on

219-427: A supermassive black hole , which may result in an active galactic nucleus . Galaxies can also have satellites in the form of dwarf galaxies and globular clusters . The constituents of a galaxy are formed out of gaseous matter that assembles through gravitational self-attraction in a hierarchical manner. At this level, the resulting fundamental components are the stars, which are typically assembled in clusters from

292-458: A variable star . An example of this is the instability strip , a region of the H-R diagram that includes Delta Scuti , RR Lyrae and Cepheid variables . The evolving star may eject some portion of its atmosphere to form a nebula, either steadily to form a planetary nebula or in a supernova explosion that leaves a remnant . Depending on the initial mass of the star and the presence or absence of

365-406: A body and an object: It is a body when referring to the frozen nucleus of ice and dust, and an object when describing the entire comet with its diffuse coma and tail . Astronomical objects such as stars , planets , nebulae , asteroids and comets have been observed for thousands of years, although early cultures thought of these bodies as gods or deities. These early cultures found

438-425: A bright image projected on one side of the dome will tend to reflect light across to the opposite side, "lifting" the black level there and so making the whole image look less realistic. Since traditional planetarium shows consisted mainly of small points of light (i.e., stars) on a black background, this was not a significant issue, but it became an issue as digital projection systems started to fill large portions of

511-542: A companion, a star may spend the last part of its life as a compact object ; either a white dwarf , neutron star , or black hole . The IAU definitions of planet and dwarf planet require that a Sun-orbiting astronomical body has undergone the rounding process to reach a roughly spherical shape, an achievement known as hydrostatic equilibrium . The same spheroidal shape can be seen on smaller rocky planets like Mars to gas giants like Jupiter . Any natural Sun-orbiting body that has not reached hydrostatic equilibrium

584-531: A far greater selection of stars. Additional projectors can be added to show twilight around the outside of the screen (complete with city or country scenes) as well as the Milky Way . Others add coordinate lines and constellations , photographic slides, laser displays, and other images. Each planet is projected by a sharply focused spotlight that makes a spot of light on the dome. Planet projectors must have gearing to move their positioning and thereby simulate

657-406: A favoured "sweet spot" for optimum viewing, centrally about a third of the way up the dome from the lowest point. Tilted domes generally have seating arranged stadium-style in straight, tiered rows; horizontal domes usually have seats in circular rows, arranged in concentric (facing center) or epicentric (facing front) arrays. Planetaria occasionally include controls such as buttons or joysticks in

730-523: A hollow ball with a light inside, and a pinhole for each star, hence the name "star ball". With some of the brightest stars (e.g. Sirius , Canopus , Vega ), the hole must be so big to let enough light through that there must be a small lens in the hole to focus the light to a sharp point on the dome. In later and modern planetarium star balls, the individual bright stars often have individual projectors, shaped like small hand-held torches, with focusing lenses for individual bright stars. Contact breakers prevent

803-806: A lot of attention. Next Zeiss planetariums were opened in Rome (1928, in Aula Ottagona , part of the Baths of Diocletian ), Chicago (1930), Osaka (1937, in the Osaka City Electricity Science Museum ). When Germany was divided into East and West Germany after the war, the Zeiss firm was also split. Part remained in its traditional headquarters at Jena , in East Germany , and part migrated to West Germany . The designer of

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876-476: A mid-size audio-visual firm on Long Island . About thirty canned programs were created for various grade levels and the public, while operators could create their own or run the planetarium live. Purchasers of the Apollo were given their choice of two canned shows, and could purchase more. A few hundred were sold, but in the late 1970s Viewlex went bankrupt for reasons unrelated to the planetarium business. During

949-509: A planetary equatorium in his Theorica Planetarum , and included instructions on how to build one. The Globe of Gottorf built around 1650 had constellations painted on the inside. These devices would today usually be referred to as orreries (named for the Earl of Orrery ). In fact, many planetariums today have projection orreries, which project onto the dome the Solar System (including

1022-408: A resolution that approaches the limit of human visual acuity . LCD projectors have fundamental limits on their ability to project true black as well as light, which has tended to limit their use in planetaria. LCOS and modified LCOS projectors have improved on LCD contrast ratios while also eliminating the "screen door" effect of small gaps between LCD pixels. "Dark chip" DLP projectors improve on

1095-529: A room, projecting images onto the white surface of a hemisphere. In August 1923, the first (Model I) Zeiss planetarium projected images of the night sky onto the white plaster lining of a 16 m hemispherical concrete dome, erected on the roof of the Zeiss works. The first official public showing was at the Deutsches Museum in Munich on October 21, 1923. Zeiss Planetarium became popular, and attracted

1168-511: A show because they allow simulation of the view from any point in space, not only the Earth-bound view which we are most familiar with. This new virtual reality capability to travel through the universe provides important educational benefits because it vividly conveys that space has depth, helping audiences to leave behind the ancient misconception that the stars are stuck on the inside of a giant celestial sphere and instead to understand

1241-448: A star ball to address some of their limitations. Digital planetarium manufacturers claim reduced maintenance costs and increased reliability from such systems compared with traditional "star balls" on the grounds that they employ few moving parts and do not generally require synchronisation of movement across the dome between several separate systems. Some planetariums mix both traditional opto-mechanical projection and digital technologies on

1314-426: A web that spans the observable universe. Galaxies have a variety of morphologies , with irregular , elliptical and disk-like shapes, depending on their formation and evolutionary histories, including interaction with other galaxies, which may lead to a merger . Disc galaxies encompass lenticular and spiral galaxies with features, such as spiral arms and a distinct halo . At the core, most galaxies have

1387-453: Is a theatre built primarily for presenting educational and entertaining shows about astronomy and the night sky , or for training in celestial navigation . A dominant feature of most planetariums is the large dome -shaped projection screen onto which scenes of stars , planets , and other celestial objects can be made to appear and move realistically to simulate their motion. The projection can be created in various ways, such as

1460-683: Is a naturally occurring physical entity , association, or structure that exists within the observable universe . In astronomy , the terms object and body are often used interchangeably. However, an astronomical body or celestial body is a single, tightly bound, contiguous entity, while an astronomical or celestial object is a complex, less cohesively bound structure, which may consist of multiple bodies or even other objects with substructures. Examples of astronomical objects include planetary systems , star clusters , nebulae , and galaxies , while asteroids , moons , planets , and stars are astronomical bodies. A comet may be identified as both

1533-587: Is classified by the IAU as a small Solar System body (SSSB). These come in many non-spherical shapes which are lumpy masses accreted haphazardly by in-falling dust and rock; not enough mass falls in to generate the heat needed to complete the rounding. Some SSSBs are just collections of relatively small rocks that are weakly held next to each other by gravity but are not actually fused into a single big bedrock . Some larger SSSBs are nearly round but have not reached hydrostatic equilibrium. The small Solar System body 4 Vesta

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1606-595: Is on the grounds of the museum. The Nechushtan pavilion is dedicated to the copper production at Timna in the southern Negev during the Chalcolithic , Bronze and Iron Age periods. The pavilion contains a reconstructed mine, smelting furnaces, and findings from the Egyptian-Midianite mining temple at Timna. The reconstructed Chalcolithic and Late Bronze Age mine displays mining tools such as stone hammers, flint blades and copper chisels, as well as

1679-399: Is sometimes used generically to describe other devices which illustrate the Solar System , such as a computer simulation or an orrery . Planetarium software refers to a software application that renders a three-dimensional image of the sky onto a two-dimensional computer screen, or in a virtual reality headset for a 3D representation. The term planetarian is used to describe a member of

1752-517: The Andromeda nebula as a different galaxy, along with many others far from the Milky Way. The universe can be viewed as having a hierarchical structure. At the largest scales, the fundamental component of assembly is the galaxy . Galaxies are organized into groups and clusters , often within larger superclusters , that are strung along great filaments between nearly empty voids , forming

1825-597: The California Academy of Sciences in Golden Gate Park , San Francisco , which operated 1952–2003. The Korkosz brothers built a large projector for the Boston Museum of Science , which was unique in being the first (and for a very long time only) planetarium to project the planet Uranus . Most planetariums ignore Uranus as being at best marginally visible to the naked eye. A great boost to

1898-538: The Islamic period (7th–15th centuries CE). Two rare vessels on display are a delicate drinking horn with two openings, known by its Greek name " rhyton ", and " Ennion 's Blue Jug" bearing the signature of its famous maker, who lived in the first half of the 1st century CE. Remnants of a glass furnace from the 13th century CE were discovered alongside the Crusader castle at Sommelaria , north of Acre . On loan from

1971-677: The Israel Antiquities Authority (IAA) is a unique Byzantine (late 6th – early 7th century) gold-glass panel from the "Birds Mosaic Mansion" in Caesarea . The ethnography and folklore section contains Judaica produced either by the Jewish diaspora in different periods, or in the Land of Israel between 1880 and 1967. The Kadman Numismatic section displays means of payment used in the country, starting those used before to

2044-661: The Landessternwarte Heidelberg-Königstuhl observatory of the University of Heidelberg , on a new and novel design, inspired by Wallace W. Atwood 's work at the Chicago Academy of Sciences and by the ideas of Walther Bauersfeld and Rudolf Straubel at Zeiss . The result was a planetarium design which would generate all the necessary movements of the stars and planets inside the optical projector, and would be mounted centrally in

2117-535: The Sun and planets up to Saturn ) in their regular orbital paths. In 1229, following the conclusion of the Fifth Crusade , Holy Roman Emperor Frederick II of Hohenstaufen brought back a tent with scattered holes representing stars or planets . The device was operated internally with a spinnable table that rotated the tent. The small size of typical 18th century orreries limited their impact, and towards

2190-399: The Sun located in the center of the Solar System . Johannes Kepler discovered Kepler's laws of planetary motion , which are properties of the orbits that the astronomical bodies shared; this was used to improve the heliocentric model. In 1584, Giordano Bruno proposed that all distant stars are their own suns, being the first in centuries to suggest this idea. Galileo Galilei was one of

2263-493: The photoelectric photometer allowed astronomers to accurately measure the color and luminosity of stars, which allowed them to predict their temperature and mass. In 1913, the Hertzsprung-Russell diagram was developed by astronomers Ejnar Hertzsprung and Henry Norris Russell independently of each other, which plotted stars based on their luminosity and color and allowed astronomers to easily examine stars. It

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2336-491: The protoplanetary disks that surround newly formed stars. The various distinctive types of stars are shown by the Hertzsprung–Russell diagram (H–R diagram)—a plot of absolute stellar luminosity versus surface temperature. Each star follows an evolutionary track across this diagram. If this track takes the star through a region containing an intrinsic variable type, then its physical properties can cause it to become

2409-515: The 1970s, the OmniMax movie system (now known as IMAX Dome) was conceived to operate on planetarium screens. More recently, some planetariums have re-branded themselves as dome theaters , with broader offerings including wide-screen or "wraparound" films, fulldome video , and laser shows that combine music with laser-drawn patterns. Learning Technologies Inc. in Massachusetts offered

2482-573: The Midianite shrine, reminding of the biblical Nehushtan , "the bronze serpent that Moses had made" ( Numbers 21:4–9; 2 Kings 18:4 ). This pavilion exhibits ancient glass vessels. The exhibition is divided into three sections, representing three eras in the history of glass production: pre-blown glass (Late Bronze Age to Hellenistic period —15th-1st centuries BCE), blown glass of the Roman and Byzantine periods (1st–7th centuries CE), and blown glass of

2555-474: The arm rests of seats to allow audience feedback that influences the show in real time . Often around the edge of the dome (the "cove") are: Traditionally, planetariums needed many incandescent lamps around the cove of the dome to help audience entry and exit, to simulate sunrise and sunset , and to provide working light for dome cleaning. More recently, solid-state LED lighting has become available that significantly decreases power consumption and reduces

2628-576: The development of coinage, and going through all historical periods until today. The Alexander Museum of Postal History and Philately recounts the history of postal service in the Land of Israel from the mid-15th century until the founding of the state in 1948. On display are envelopes, letters, photographs, posters, mailboxes and telephones, as well as a mail truck from 1949. The philatelic wing displays valuable and rare stamps. Planetarium A planetarium ( pl. : planetariums or planetaria )

2701-417: The dome with bright objects (e.g., large images of the sun in context). For this reason, modern planetarium domes are often not painted white but rather a mid grey colour, reducing reflection to perhaps 35-50%. This increases the perceived level of contrast. A major challenge in dome construction is to make seams as invisible as possible. Painting a dome after installation is a major task, and if done properly,

2774-452: The dome) in every elementary school in Japan. Phillip Stern, as former lecturer at New York City 's Hayden Planetarium , had the idea of creating a small planetarium which could be programmed. His Apollo model was introduced in 1967 with a plastic program board, recorded lecture, and film strip. Unable to pay for this himself, Stern became the head of the planetarium division of Viewlex ,

2847-438: The end of that century a number of educators attempted to create a larger sized version. The efforts of Adam Walker (1730–1821) and his sons are noteworthy in their attempts to fuse theatrical illusions with education. Walker's Eidouranion was the heart of his public lectures or theatrical presentations. Walker's son describes this "Elaborate Machine" as "twenty feet high, and twenty-seven in diameter: it stands vertically before

2920-576: The first digital planetarium projector displaying computer graphics ( Hansen planetarium , Salt Lake City, Utah)—the Digistar I projector used a vector graphics system to display starfields as well as line art . This gives the operator great flexibility in showing not only the modern night sky as visible from Earth , but as visible from points far distant in space and time. The newest generations of planetarium projectors, beginning with Digistar 3 , offer fulldome video technology. This allows for

2993-579: The first astronomers to use telescopes to observe the sky, in 1610 he observed the four largest moons of Jupiter , now named the Galilean moons . Galileo also made observations of the phases of Venus , craters on the Moon , and sunspots on the Sun. Astronomer Edmond Halley was able to successfully predict the return of Halley's Comet , which now bears his name, in 1758. In 1781, Sir William Herschel discovered

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3066-477: The first easily portable planetarium in 1977. Philip Sadler designed this patented system which projected stars, constellation figures from many mythologies , celestial coordinate systems, and much else, from removable cylinders (Viewlex and others followed with their own portable versions). When Germany reunified in 1989, the two Zeiss firms did likewise, and expanded their offerings to cover many different size domes. In 1983, Evans & Sutherland installed

3139-610: The first planetariums for Zeiss, Walther Bauersfeld , also migrated to West Germany with the other members of the Zeiss management team. There he remained on the Zeiss West management team until his death in 1959. The West German firm resumed making large planetariums in 1954, and the East German firm started making small planetariums a few years later. Meanwhile, the lack of planetarium manufacturers had led to several attempts at construction of unique models, such as one built by

3212-908: The floor. The largest planetarium in the Western Hemisphere is the Jennifer Chalsty Planetarium at Liberty Science Center in New Jersey , its dome measuring 27 meters in diameter. The Birla Planetarium in Kolkata, India is the largest by seating capacity, having 630 seats. In North America, the Hayden Planetarium at the American Museum of Natural History in New York City has the greatest number of seats, at 423. The term planetarium

3285-455: The horizon of the dome are arranged to blend together seamlessly. Digital projection systems all work by creating the image of the night sky as a large array of pixels . Generally speaking, the more pixels a system can display, the better the viewing experience. While the first generation of digital projectors were unable to generate enough pixels to match the image quality of the best traditional "star ball" projectors, high-end systems now offer

3358-521: The human eye were discovered, and new telescopes were made that made it possible to see astronomical objects in other wavelengths of light. Joseph von Fraunhofer and Angelo Secchi pioneered the field of spectroscopy , which allowed them to observe the composition of stars and nebulae, and many astronomers were able to determine the masses of binary stars based on their orbital elements . Computers began to be used to observe and study massive amounts of astronomical data on stars, and new technologies such as

3431-618: The maintenance requirement as lamps no longer have to be changed on a regular basis. The world's largest mechanical planetarium is located in Monico, Wisconsin. The Kovac Planetarium . It is 22 feet in diameter and weighs two tons. The globe is made of wood and is driven with a variable speed motor controller. This is the largest mechanical planetarium in the world, larger than the Atwood Globe in Chicago (15 feet in diameter) and one third

3504-530: The movements of the bodies very important as they used these objects to help navigate over long distances, tell between the seasons, and to determine when to plant crops. During the Middle-Ages , cultures began to study the movements of these bodies more closely. Several astronomers of the Middle-East began to make detailed descriptions of stars and nebulae, and would make more accurate calendars based on

3577-559: The movements of these stars and planets. In Europe , astronomers focused more on devices to help study the celestial objects and creating textbooks, guides, and universities to teach people more about astronomy. During the Scientific Revolution , in 1543, Nicolaus Copernicus's heliocentric model was published. This model described the Earth , along with all of the other planets as being astronomical bodies which orbited

3650-503: The new planet Uranus , being the first discovered planet not visible by the naked eye. In the 19th and 20th century, new technologies and scientific innovations allowed scientists to greatly expand their understanding of astronomy and astronomical objects. Larger telescopes and observatories began to be built and scientists began to print images of the Moon and other celestial bodies on photographic plates. New wavelengths of light unseen by

3723-402: The night sky. Finally, in most traditional projectors the various overlaid projection systems are incapable of proper occultation . This means that a planet image projected on top of a star field (for example) will still show the stars shining through the planet image, degrading the quality of the viewing experience. For related reasons, some planetariums show stars below the horizon projecting on

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3796-402: The planets' movements. These can be of these types:- Despite offering a good viewer experience, traditional star ball projectors suffer several inherent limitations. From a practical point of view, the low light levels require several minutes for the audience to "dark adapt" its eyesight. "Star ball" projection is limited in education terms by its inability to move beyond an Earth-bound view of

3869-578: The popularity of the planetarium worldwide was provided by the Space Race of the 1950s and 60s when fears that the United States might miss out on the opportunities of the new frontier in space stimulated a massive program to install over 1,200 planetariums in U.S. high schools. Armand Spitz recognized that there was a viable market for small inexpensive planetaria. His first model, the Spitz A,

3942-462: The professional staff of a planetarium. The ancient Greek polymath Archimedes is attributed with creating a primitive planetarium device that could predict the movements of the Sun and the Moon and the planets. The discovery of the Antikythera mechanism proved that such devices already existed during antiquity , though likely after Archimedes' lifetime. Campanus of Novara described

4015-423: The projection of any image. Planetarium domes range in size from 3 to 35 m in diameter , accommodating from 1 to 500 people. They can be permanent or portable, depending on the application. The realism of the viewing experience in a planetarium depends significantly on the dynamic range of the image, i.e., the contrast between dark and light. This can be a challenge in any domed projection environment, because

4088-473: The projectors from projecting below the "horizon". The star ball is usually mounted so it can rotate as a whole to simulate the Earth's daily rotation, and to change the simulated latitude on Earth. There is also usually a means of rotating to produce the effect of precession of the equinoxes . Often, one such ball is attached at its south ecliptic pole. In that case, the view cannot go so far south that any of

4161-499: The resulting blank area at the south is projected on the dome. Some star projectors have two balls at opposite ends of the projector like a dumbbell . In that case all stars can be shown and the view can go to either pole or anywhere between. But care must be taken that the projection fields of the two balls match where they meet or overlap. Smaller planetarium projectors include a set of fixed stars, Sun, Moon, and planets, and various nebulae . Larger projectors also include comets and

4234-428: The same dome. In a fully digital planetarium, the dome image is generated by a computer and then projected onto the dome using a variety of technologies including cathode-ray tube , LCD , DLP , or laser projectors. Sometimes a single projector mounted near the centre of the dome is employed with a fisheye lens to spread the light over the whole dome surface, while in other configurations several projectors around

4307-409: The seams can be made almost to disappear. Traditionally, planetarium domes were mounted horizontally, matching the natural horizon of the real night sky. However, because that configuration requires highly inclined chairs for comfortable viewing "straight up", increasingly domes are being built tilted from the horizontal by between 5 and 30 degrees to provide greater comfort. Tilted domes tend to create

4380-594: The size of the Hayden. Some new planetariums now feature a glass floor , which allows spectators to stand near the center of a sphere surrounded by projected images in all directions, giving the impression of floating in outer space . For example, a small planetarium at AHHAA in Tartu , Estonia features such an installation, with special projectors for images below the feet of the audience, as well as above their heads. Traditional planetarium projection apparatus use

4453-461: The sky tonight?", or shows which pick up on topical issues such as a religious festival (often the Christmas star ) linked to the night sky, have been popular. Live format is preferred by many venues as a live speaker or presenter can answer questions raised by the audience. Since the early 1990s, fully featured 3-D digital planetariums have added an extra degree of freedom to a presenter giving

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4526-465: The spectators, and its globes are so large, that they are distinctly seen in the most distant parts of the Theatre. Every Planet and Satellite seems suspended in space, without any support; performing their annual and diurnal revolutions without any apparent cause". Other lecturers promoted their own devices: R E Lloyd advertised his Dioastrodoxon, or Grand Transparent Orrery, and by 1825 William Kitchener

4599-476: The standard DLP design and can offer relatively inexpensive solution with bright images, but the black level requires physical baffling of the projectors. As the technology matures and reduces in price, laser projection looks promising for dome projection as it offers bright images, large dynamic range and a very wide color space . Worldwide, most planetariums provide shows to the general public. Traditionally, shows for these audiences with themes such as "What's in

4672-618: The true layout of the Solar System and beyond. For example, a planetarium can now 'fly' the audience towards one of the familiar constellations such as Orion , revealing that the stars which appear to make up a co-ordinated shape from an Earth-bound viewpoint are at vastly different distances from Earth and so not connected, except in human imagination and mythology . For especially visual or spatially aware people, this experience can be more educationally beneficial than other demonstrations. Astronomical object An astronomical object , celestial object , stellar object or heavenly body

4745-460: The typical marks they left on the rock. Four smelting furnaces are on display: In the 14th century BCE, the Egyptian pharaohs dispatched mining expeditions to Timna. Alongside expert metalsmiths from the Land of Midian , they extracted copper at Timna until the early 12th century BCE. This pavilion houses a Midianite temple model. Of special interest is the copper snake with gilded head found in

4818-399: The various condensing nebulae. The great variety of stellar forms are determined almost entirely by the mass, composition and evolutionary state of these stars. Stars may be found in multi-star systems that orbit about each other in a hierarchical organization. A planetary system and various minor objects such as asteroids, comets and debris, can form in a hierarchical process of accretion from

4891-432: The walls below the dome or on the floor, or (with a bright star or a planet) shining in the eyes of someone in the audience. However, the new breed of Optical-Mechanical projectors using fiber-optic technology to display the stars show a much more realistic view of the sky. An increasing number of planetariums are using digital technology to replace the entire system of interlinked projectors traditionally employed around

4964-635: Was completed in 1781. In 1905 Oskar von Miller (1855–1934) of the Deutsches Museum in Munich commissioned updated versions of a geared orrery and planetarium from M Sendtner, and later worked with Franz Meyer, chief engineer at the Carl Zeiss optical works in Jena , on the largest mechanical planetarium ever constructed, capable of displaying both heliocentric and geocentric motion. This

5037-468: Was designed to project stars from a dodecahedron , thus reducing machining expenses in creating a globe. Planets were not mechanized, but could be shifted by hand. Several models followed with various upgraded capabilities, until the A3P, which projected well over a thousand stars, had motorized motions for latitude change, daily motion, and annual motion for Sun, Moon (including phases), and planets. This model

5110-407: Was displayed at the Deutsches Museum in 1924, construction work having been interrupted by the war. The planets travelled along overhead rails, powered by electric motors: the orbit of Saturn was 11.25 m in diameter. 180 stars were projected onto the wall by electric bulbs. While this was being constructed, von Miller was also working at the Zeiss factory with German astronomer Max Wolf , director of

5183-536: Was found that stars commonly fell on a band of stars called the main-sequence stars on the diagram. A refined scheme for stellar classification was published in 1943 by William Wilson Morgan and Philip Childs Keenan based on the Hertzsprung-Russel Diagram. Astronomers also began debating whether other galaxies existed beyond the Milky Way , these debates ended when Edwin Hubble identified

5256-536: Was installed in hundreds of high schools, colleges, and even small museums from 1964 to the 1980s. Japan entered the planetarium manufacturing business in the 1960s, with Goto and Minolta both successfully marketing a number of different models. Goto was particularly successful when the Japanese Ministry of Education put one of their smallest models, the E-3 or E-5 (the numbers refer to the metric diameter of

5329-486: Was offering his Ouranologia, which was 42 feet (13 m) in diameter. These devices most probably sacrificed astronomical accuracy for crowd-pleasing spectacle and sensational and awe-provoking imagery. The oldest still-working planetarium can be found in the Frisian city of Franeker . It was built by Eise Eisinga (1744–1828) in the living room of his house. It took Eisinga seven years to build his planetarium, which

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