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90-736: The museum's collection dates to an 1881 gift to the Kalamazoo School Board of corals, shells, and rocks from Horace M. Peck, a local banker. In its early years, the museum acquired natural history specimens, ethnographic materials, and antiquities. Currently, the collection includes over 50,000 items. The museum has a state-of-the-art, 109-seat planetarium that screens a variety of presentations and programs for school groups and other public audiences. The museum, whose special exhibitions galleries feature an ever-changing variety of traveling exhibits, also features several permanent exhibits. These include: This Michigan museum-related article

180-475: 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

270-425: 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

360-462: A crusade, and began organizing Crusading armies led by Andrew II of Hungary and Leopold VI of Austria , soon to be joined by John of Brienne , titular King of Jerusalem . An initial campaign in late 1217 in Syria was inconclusive, and Andrew departed. A German army led by cleric Oliver of Paderborn , and a mixed army of Dutch , Flemish and Frisian soldiers led by William I of Holland , then joined

450-444: A failure of the crops in 1201–1202, and famine and pestilence ensued. People abandoned themselves to atrocious practices, habitually resorting to cannibalism. Violent earthquakes, felt as far away as Syria and Armenia, devastated whole cities, and increased the general misery. After naval raids on Rosetta in 1204 and Damietta in 1211, the chief concern of al-Adil was Egypt. He was willing to make concessions to avoid war, and favoured

540-526: 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

630-406: 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

720-569: A former classmate of the pope's. He was met with bitter complaints by the clergy, accusing the legate of encroaching on their domains. Philip II of France supported his clergy, and Innocent III realized the Robert's zeal was a threat to the success of the Crusade. On 11 November 1215, the Fourth Lateran Council was convened. The prelates of France presented their grievances, many well-founded, and

810-523: 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

900-766: 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

990-472: 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

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1080-499: 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

1170-408: 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

1260-517: 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

1350-505: 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

1440-448: 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

1530-455: A two-prong attack. In Syria, Andrew's forces would engage al-Mu'azzam , son of Al-Adil, at the stronghold of Nablus . At the same time, the fleet was to attack the port city of Damietta , wresting Egypt from the Muslims and enabling the conquest of the remainder of Syria and Palestine. This plan was abandoned at Acre due to the lack of manpower and ships. Instead, in anticipation of reinforcements,

1620-699: A veteran of the Fourth Crusade, would also return to the Holy Land with the Fifth Crusade. French canon Jacques de Vitry had come under the influence of the saintly Marie of Oignies and preached the Albigensian Crusade after 1210. He arrived at his new position as Bishop of Acre in 1216 and shortly thereafter Honorius III tasked him with preaching the Crusade in the Latin settlements of Syria, made difficult with

1710-589: Is a stub . You can help Misplaced Pages by expanding it . Planetarium A planetarium ( pl. : planetariums or planetaria ) 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

1800-399: 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

1890-609: The Almohads . There was little appetite in Europe for a new Crusade. In Jerusalem, John of Brienne became the effective ruler of the kingdom through his marriage to Maria of Montferrat . In 1212, Isabella II of Jerusalem was proclaimed queen of Jerusalem shortly after her birth, and her father John became regent. Antioch was consumed with the War of the Antiochene Succession , begun with

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1980-574: 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

2070-633: 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

2160-525: 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

2250-503: 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

2340-504: The Crusade in Acre , with a goal of first conquering Egypt, viewed as the key to Jerusalem. There, cardinal Pelagius Galvani arrived as papal legate and de facto leader of the Crusade, supported by John of Brienne and the masters of the Templars , Hospitallers and Teutonic Knights . Holy Roman Emperor Frederick II , who had taken the cross in 1215, did not participate as promised. Following

2430-626: The Crusader states in the Levant The Fifth Crusade (September 1217 - August 29, 1221) was a campaign in a series of Crusades by Western Europeans to reacquire Jerusalem and the rest of the Holy Land by first conquering Egypt , ruled by the powerful Ayyubid sultanate, led by al-Adil , brother of Saladin . After the failure of the Fourth Crusade , Innocent III again called for

2520-504: The Crusaders decided to go to the Holy Land by their traditional sea journey. The fleet made their first stop at Dartmouth on the southern coast of England. There they elected their leaders and the laws by which they would organize their venture. From there, led by William I of Holland , they continued on their way south to Lisbon. As in previous crusading seaborne journeys, the fleet was dispersed by storms and only gradually managed to reach

2610-521: The Crusaders, capturing al-Qualai'ah , besieging Krak des Chevaliers and advancing to Tripoli , before accepting an indemnity from Bohemond IV in exchange for peace. Az-Zahir maintained an alliance with both Antioch and Kaykaus I , the Seljuk sultan of Rûm , to check the influence of Leo I of Armenia , as well as to keep his options open to challenge his uncle. Az-Zahir died in 1216, leaving as his successor al-Aziz Muhammad , his 3-year-old son, whose mother

2700-454: The Crusaders, he guarded the approaches to Damascus while al-Mu'azzam was sent to Nablus to protect Jerusalem. The Crusaders were camped near Acre at Tel Afek , and on 3 November 1217 began to traverse the plain of Esdraelon towards 'Ain Jalud , expecting an ambush. Upon seeing the strength of the Crusaders, al-Adil withdrew to Beisan against the wishes of al-Mu'azzam who wanted to attack from

2790-587: The Crusaders’ Egyptian plan, these diversions were useful in stretching the resources of the sultanate that controlled the Levant with an uneasy cooperation. The first to take up the cross in the Fifth Crusade was King Andrew II of Hungary . Andrew II had been called on by the pope in July 1216 to fulfill his father Béla III's vow to lead a crusade, and finally agreed, having postponed three times earlier. Andrew, who

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2880-555: The Georgian state to its zenith of power and prestige in the Middle Ages. Under her rule, Georgia challenged Ayyubid rule in eastern Anatolia. Tamar died in 1213 and was succeeded by her son George IV of Georgia . In the late 1210s, according to the Georgian chronicles, he began making preparations for a campaign in the Holy Land to support the Franks. His plans were cut short by the invasion of

2970-421: The Holy Land (1095–1291) Later Crusades (1291–1717) Northern (1147–1410) Against Christians (1209–1588) Popular (1096–1320) Period post-First Crusade Second Crusade Period post-Second Crusade Third Crusade Period post-Third Crusade Fourth Crusade Fifth Crusade Sixth Crusade and aftermath Seventh Crusade End of

3060-544: The Holy Land.” In April 1213, Innocent III issued his papal bull Quia maior , calling all of Christendom to join a new Crusade. This was followed by a conciliar decree, the Ad Liberandam, in 1215. The attendant papal instructions engaged a new enterprise to recover Jerusalem while establishing Crusading norms that were to last nearly a century. The message of the Crusade was preached in France by legate Robert of Courçon ,

3150-729: The Italian maritime states of Venice and Pisa, both for trading reasons and to preclude them from supporting further crusades. Most of his reign was conducted under truces with the Christians, and he constructed a new fortress at Mount Tabor , to buttress the defenses of Jerusalem and Damascus. Most of his conflicts in Syria were with the Knights Hospitaller at Krak des Chevaliers or with Bohemond IV of Antioch , and were dealt with by his nephew az-Zahir Ghazi. Only once, in 1207, did he directly confront

3240-525: The Mongols in 1220. After the death of George IV, his sister Rusudan of Georgia notified the pope that Georgia was unable to fulfill its promises. Saladin had died in 1193 and was succeeded in most of his domain by his brother al-Adil , who was the patriarch of all successive Ayyubid sultans of Egypt. Saladin's son az-Zahir Ghazi retained his leadership in Aleppo . An exceptionally low Nile River resulted in

3330-522: The Muslims as impregnable. A battle fought on 3 December 1217 was soon abandoned by the leaders, only to be revisited by the Templars and Hospitallers. Met with Greek fire, the siege was abandoned on 7 December 1217. A third sortie by the Hungarians, possibly led by Andrew's nephew, met disaster at Mashghara . The small force was decimated, and the few survivors returned to Acre on Christmas Eve. Thus ended what

3420-677: The Portuguese city of Lisbon after making a stopover at the famous shrine of Santiago de Compostela . At their arrival in Portugal, the Bishop of Lisbon attempted to persuade the Crusaders to help them capture the Almohad controlled city of Alcácer do Sal . The Frisians, however, refused on account of Innocent III's disqualification of the venture at the Fourth Lateran Council. The other members of

3510-460: The Venetian fleet, the largest European fleet of the times. Andrew and his troops embarked from Split on 23 August 1217. The Hungarian army landed on 9 October 1217 on Cyprus from where they sailed to Acre and joined John of Brienne, Raoul of Merencourt and Hugh I of Cyprus . Until his return to Hungary, King Andrew remained the leader of Christian forces in the Fifth Crusade. In October 1217,

3600-474: 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

3690-475: The armies was estimated at more than 32,000, including more than 10,000 knights. It was described by a contemporaneous Arab historian as: "This year, an infinite number of warriors left from Rome the great and other countries of the West." The Crusader force was also prepared to use the latest siege technology, including counterweight trebuchets. The departure of the Crusaders began finally in early July 1217. Many of

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3780-539: The city took defensive measures, and received reinforcements from al-Mujahid Shirkuh , the Ayyubid emir of Homs . Without engaging the enemy, the Crusaders returned to the camp near Acre, crossing over Jacob's Ford . Andrew II did not return to the battlefield, preferring to remain in Acre collecting relics. Now under the command of John of Brienne, as supported by Bohemond IV, the Hungarians moved against Mount Tabor , regarded by

3870-574: The coast of southern France and wintered in Civitavecchia in Italy in 1217–1218, before continuing on their way to Acre. In the north, Ingi II of Norway took the cross in 1216, only to die the next spring, and the eventual Scandinavian expedition was of little consequence. Innocent III had managed to secure the participation of the Kingdom of Georgia in the Crusade. Tamar of Georgia , queen since 1184, led

3960-411: The date for the beginning of the expedition. In Europe, the troubadours were equally adept in awakening the interest in the Crusade. These included Elias Cairel , a veteran of the Fourth Crusade, Pons de Capduelh , later joining the Crusade in 1220, and Aimery de Pégulhan , who implored by verse a young William VI of Montferrat to follow in his father's footsteps and take the cross. The strength of

4050-477: The death of Bohemond III , not to be resolved until 1219. Before the arrival of John of Brienne in Acre in 1210, the local Christians had refused to renew their truce the Ayyubids. The next year, John negotiated with the aging sultan al-Adil a new truce between the kingdom and the sultanate to last through 1217. At the same time, in light of the strength of the Muslims and their renewed fortifications, John also asked

4140-417: 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,

4230-448: 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 ,

4320-438: 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

4410-463: The expenses of a Crusader, but did not go on the Crusade themselves. In order to protect Raoul of Merencourt , the Latin patriarch of Jerusalem, on his return trip to the kingdom, Innocent III tasked John of Brienne to provide escort. As John was in conflict with Leo I of Armenia and Hugh I of Cyprus , the pope ordered them to reconcile their differences before the Crusaders reached the Holy Land. Innocent III died on 16 July 1216 and Honorius III

4500-571: 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

4590-477: 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

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4680-598: 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

4770-619: The fleet, however, were convinced by the Portuguese and started the siege of Alcácer do Sal in August 1217. The Crusaders finally captured the city with the help of the Knights Templar and Knights Hospitaller , on October 1217. A group of Frisians who refused to aid the Portuguese with their siege plans against Alacácer do Sal, preferred to raid several coastal towns on their way to the Holy Land. They attacked Faro , Rota , Cádiz and Ibiza , gaining much booty thereby. They thereafter followed

4860-855: 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

4950-552: The heights of Nain . Again against the wishes of his son, Al-Adil abandoned Beisan which soon fell to the Crusaders who pillaged the city. He continued his retreat to Ajlun , ordering al-Mu'azzam to protect Jerusalem from the heights of Lubban , near Shiloh . Al-Adil continued to Damascus, stopping at Marj al-Saffar . On 10 November 1217, the Crusaders crossed the Jordan River at the Jisr el-Majami , threatening Damascus. The governor of

5040-455: 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

5130-557: The leaders of the expedition held a war council there, presided by Andrew II. Representing the military orders were the masters Guérin de Montaigu of the Hospitallers, Guillaume de Chartres of the Templars, and Hermann of Salza of the Teutonic Knights . Additional attendees included Leopold VI of Austria, Otto I of Merania, Walter II of Avesnes , and numerous archbishops and bishops. The war plan of John of Brienne envisioned

5220-603: 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

5310-402: 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

5400-526: The objective was to keep the enemy occupied in a series of small engagements, perhaps going as far as Damascus. The Muslims knew that the Crusaders were coming in 1216 with the exodus of merchants from Alexandria. Once the host gathered at Acre, Al-Adil began operations in Syria, leaving the bulk of his forces in Egypt under his eldest son and viceroy Al-Kamil . He personally led a small contingent to support al-Mu'azzam, then emir of Damascus . With too few to engage

5490-560: The papacy, as the First Crusade should have been, to avoid the mistakes of the Fourth Crusade , which had been taken over by the Venetians. He planned to meet with the Crusaders at Brindisi and Messina for departure on 1 June 1217, and prohibited trade with the Muslims in order to ensure that the Crusaders would have ships and weapons, renewing an 1179 edict. Every Crusader would receive an indulgence as well as those who simply helped pay

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5580-402: 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

5670-515: The pope for help. There was no real force among the Syrian Franks, with many of the deployed knights returning home. If a new Crusade were to begin, it must come from Europe. Innocent III had hoped to mount such a Crusade to the Holy Land, never forgetting the goal of restoring Jerusalem to Christian control. The pathos of the Children's Crusade only nerved him to fresh efforts. But for Innocent, this tragedy had its moral: “the very children put us to shame, while we sleep they go forth gladly to conquer

5760-423: The pope pleaded for them to forgive the legate's indiscretions. In the end, very few Frenchmen took part in the expedition of 1217, unwilling to go in the company of Germans and Hungarians, with France represented by Aubrey of Reims and the bishops of Limoges and Bayeux , Jean de Veyrac and Robert des Ablèges. At the council, Innocent III called for the recovery of the Holy Land. Innocent wanted it to be led by

5850-405: 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,

5940-403: 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

6030-423: 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

6120-421: 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

6210-527: The rampant corruption at the port cities. Oliver of Paderborn preached the Crusade in Germany and had great success in recruitment. In July 1216, Honorius III called on Andrew II of Hungary to fulfill his father's vow to lead a Crusade. Like many other rulers, the pope's former pupil, Frederick II of Germany , had taken an oath to embark for the Holy Land in 1215 and appealed to German nobility to join. But Frederick II hung back, with his crown still in contention with Otto IV , and Honorius repeatedly put off

6300-499: 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

6390-464: The retreat from Damietta—leaving Egypt altogether—and an eight-year truce. The Fifth Crusade ended in September 1221, a Crusader defeat that failed to achieve its goals. By 1212, Innocent III had been pope for 14 years and faced the disappointment of the Fourth Crusade and its inability to recover Jerusalem, the on-going Albigensian Crusade , begun in 1209, and the popular fervor of the Children's Crusade of 1212. The Latin Empire of Constantinople

6480-428: 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

6570-409: 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

6660-586: 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

6750-456: 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

6840-460: 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

6930-476: 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

7020-486: The successful siege of Damietta in 1218–1219, the Crusaders occupied the port for two years. Al-Kamil , now sultan of Egypt, offered attractive peace terms, including the restoration of Jerusalem to Christian rule. The sultan was rebuked by Pelagius several times, and the Crusaders marched south towards Cairo in July 1221. En route, they attacked a stronghold of al-Kamil at the battle of Mansurah , but they were defeated and forced to surrender. The terms of surrender included

7110-602: 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. Fifth Crusade Crusaders: Levant: Military orders: Muslim forces: In

7200-432: 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

7290-455: Was Dayfa Khatun , al-Adil's daughter. Saladin's eldest son, al-Afdal , emerged to make a bid for Aleppo, enlisting the help of Kaykaus I, who also had designs on the region. In 1218, al-Afdal and Kaykaus invaded Aleppo and advanced on the capital. The situation was resolved when al-Ashraf , al-Adil's third son, routed the Seljuk army, which remained a menace until the death of Kaykaus in 1220. Given

7380-613: 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

7470-554: Was consecrated as pope the next week. The Crusade dominated the early part of his papacy. The next year, he crowned Peter II of Courtenay as Latin Emperor, who was captured on his eastward journey in Epirus and died in confinement. Robert of Courçon was sent as spiritual advisor to the French fleet, but subordinate to newly-chosen papal delegate Pelagius of Albano . Bishop Walter II of Autun ,

7560-465: 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

7650-407: 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

7740-654: Was established, with the emperor Baldwin I essentially elected by the Venetians. (The imperial crown was at first offered to doge Enrico Dandolo , who refused it.) The first Latin Patriarch of Constantinople , the Venetian Thomas Morosini , was contested by the pope as uncanonical. The ongoing situation in Europe was chaotic. Philip of Swabia was locked in a dispute of the throne in Germany with Otto of Brunswick . Innocent III's attempts to reconcile their differences

7830-525: 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

7920-481: 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

8010-455: Was rendered moot with Philip's assassination on 21 June 1208. Otto was crowned Holy Roman Emperor and fought against the pope, resulting in his excommunication. France was heavily invested in the Albigensian Crusade and was quarreling with John Lackland , resulting in the Anglo-French war of 1213–1214. Sicily was ruled by the child-king Henry II and Spain was occupied in their crusade against

8100-493: Was reputed to have designs on becoming Latin emperor, mortgaged his estates to finance the Crusade. In July 1217, Andrew departed from Zagreb , accompanied by Leopold VI of Austria and Otto I, Duke of Merania . King Andrew's army was so large—at least 20,000 mounted soldiers and even much more "uncountable" infantrymen—that most of it stayed behind when Andrew and his men embarked in Split two months later. They were transported by

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