Chamaeleon ( / k ə ˈ m iː l i ən / ) is a small constellation in the deep southern sky . It is named after the chameleon , a kind of lizard . It was first defined in the 16th century.
70-490: Chamaeleon was one of twelve constellations created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman . It first appeared on a 35-cm diameter celestial globe published in 1597 (or 1598) in Amsterdam by Plancius and Jodocus Hondius . Johann Bayer was the first uranographer to put Chamaeleon in a celestial atlas. It was one of many constellations created by European explorers in
140-421: A nautical almanac , can be used to calculate the time at zero longitude (see Greenwich Mean Time ). Reliable marine chronometers were unavailable until the late 18th century and not affordable until the 19th century. For about a hundred years, from about 1767 until about 1850, mariners lacking a chronometer used the method of lunar distances to determine Greenwich time to find their longitude. A mariner with
210-433: A sextant and using sight reduction tables to correct for height of eye and atmospheric refraction. The height of Polaris in degrees above the horizon is the latitude of the observer, within a degree or so. Similar to latitude, the longitude of a place on Earth is the angular distance east or west of the prime meridian or Greenwich meridian . Longitude is usually expressed in degrees (marked with °) ranging from 0° at
280-922: A Camel), Cancer Minor the Small Crab, Euphrates Fluvius et Tigris Fluvius the Rivers Euphrates and Tigris, Gallus the Cock, Jordanis Fluvius the River Jordan, Monoceros the Unicorn and Sagitta Australis the Southern Arrow. Of the latter constellations, only Camelopardalis and Monoceros are still found on modern star charts, and recognized by the IAU . The minor planet 10648 Plancius commemorates his contributions in celestial and terrestrial cartography. Navigation Navigation
350-726: A Portuguese expedition commanded by Vasco da Gama reached India by sailing around Africa, opening up direct trade with Asia . Soon, the Portuguese sailed further eastward, to the Spice Islands in 1512, landing in China one year later. The first circumnavigation of the earth was completed in 1522 with the Magellan-Elcano expedition , a Spanish voyage of discovery led by Portuguese explorer Ferdinand Magellan and completed by Spanish navigator Juan Sebastián Elcano after
420-691: A chronometer could check its reading using a lunar determination of Greenwich time. In navigation, a rhumb line (or loxodrome) is a line crossing all meridians of longitude at the same angle, i.e. a path derived from a defined initial bearing. That is, upon taking an initial bearing, one proceeds along the same bearing, without changing the direction as measured relative to true or magnetic north. Most modern navigation relies primarily on positions determined electronically by receivers collecting information from satellites. Most other modern techniques rely on finding intersecting lines of position or LOP. A line of position can refer to two different things, either
490-478: A distance produces a circle or arc of position. Circles, arcs, and hyperbolae of positions are often referred to as lines of position. If the navigator draws two lines of position, and they intersect he must be at that position. A fix is the intersection of two or more LOPs. If only one line of position is available, this may be evaluated against the dead reckoning position to establish an estimated position. Lines (or circles) of position can be derived from
560-612: A few meters using time signals transmitted along a line of sight by radio from satellites . Receivers on the ground with a fixed position can also be used to calculate the precise time as a reference for scientific experiments. As of October 2011, only the United States NAVSTAR Global Positioning System (GPS) and the Russian GLONASS are fully globally operational GNSSs. The European Union 's Galileo positioning system
630-402: A line on a chart or a line between the observer and an object in real life. A bearing is a measure of the direction to an object. If the navigator measures the direction in real life, the angle can then be drawn on a nautical chart and the navigator will be somewhere on that bearing line on the chart. In addition to bearings, navigators also often measure distances to objects. On the chart,
700-450: A number of stars in succession to give a series of overlapping lines of position. Where they intersect is the celestial fix. The Moon and Sun may also be used. The Sun can also be used by itself to shoot a succession of lines of position (best done around local noon) to determine a position. In order to accurately measure longitude, the precise time of a sextant sighting (down to the second, if possible) must be recorded. Each second of error
770-399: A particularly good navigation system for ships and aircraft that might be flying at a distance from land. RDFs works by rotating a directional antenna and listening for the direction in which the signal from a known station comes through most strongly. This sort of system was widely used in the 1930s and 1940s. RDF antennas are easy to spot on German World War II aircraft, as loops under
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#1732772125770840-418: A radio time signal. Times and frequencies of radio time signals are listed in publications such as Radio Navigational Aids . The second critical component of celestial navigation is to measure the angle formed at the observer's eye between the celestial body and the sensible horizon. The sextant, an optical instrument, is used to perform this function. The sextant consists of two primary assemblies. The frame
910-400: A single object," "two or more bearings," "tangent bearings," and "two or more ranges." Radar can also be used with ECDIS as a means of position fixing with the radar image or distance/bearing overlaid onto an Electronic nautical chart . Parallel indexing is a technique defined by William Burger in the 1957 book The Radar Observer's Handbook . This technique involves creating a line on
980-404: A sufficient depth of water below the hull as well as a consideration for squat . It may also involve navigating a ship within a river, canal or channel in close proximity to land. A military navigation team will nearly always consist of several people. A military navigator might have bearing takers stationed at the gyro repeaters on the bridge wings for taking simultaneous bearings, while
1050-413: A variety of sources: There are some methods seldom used today such as "dipping a light" to calculate the geographic range from observer to lighthouse. Methods of navigation have changed through history. Each new method has enhanced the mariner's ability to complete his voyage. One of the most important judgments the navigator must make is the best method to use. Some types of navigation are depicted in
1120-453: Is Pulsar navigation , which compares the X-ray bursts from a collection of known pulsars in order to determine the position of a spacecraft. This method has been tested by multiple space agencies, such as NASA and ESA . A radio direction finder or RDF is a device for finding the direction to a radio source. Due to radio's ability to travel very long distances "over the horizon", it makes
1190-533: Is a blue-white hued star of magnitude 4.2, 271 light-years from Earth. Gamma Chamaeleontis is a red-hued giant star of magnitude 4.1, 413 light-years from Earth. The other bright star in Chamaeleon is Delta Chamaeleontis , a wide double star . The brighter star is Delta Chamaeleontis , a blue-hued star of magnitude 4.4. Delta Chamaeleontis , the dimmer component, is an orange-hued giant star of magnitude 5.5. They both lie about 350 light years away. Chamaeleon
1260-446: Is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another. The field of navigation includes four general categories: land navigation, marine navigation , aeronautic navigation, and space navigation. It is also the term of art used for the specialized knowledge used by navigators to perform navigation tasks. All navigational techniques involve locating
1330-436: Is a quartz crystal oscillator. The quartz crystal is temperature compensated and is hermetically sealed in an evacuated envelope. A calibrated adjustment capability is provided to adjust for the aging of the crystal. The chronometer is designed to operate for a minimum of one year on a single set of batteries. Observations may be timed and ship's clocks set with a comparing watch, which is set to chronometer time and taken to
1400-425: Is a rigid triangular structure with a pivot at the top and a graduated segment of a circle, referred to as the "arc", at the bottom. The second component is the index arm, which is attached to the pivot at the top of the frame. At the bottom is an endless vernier which clamps into teeth on the bottom of the "arc". The optical system consists of two mirrors and, generally, a low power telescope. One mirror, referred to as
1470-770: Is also the location of Cha 110913 , a unique dwarf star or proto solar system. In 1999, a nearby open cluster was discovered centered on the star η Chamaeleontis . The cluster, known as either the Eta Chamaeleontis cluster or Mamajek 1, is 8 million years old, and lies 316 light years from Earth. The constellation contains a number of molecular clouds (the Chamaeleon dark clouds ) that are forming low-mass T Tauri stars . The cloud complex lies some 400 to 600 light years from Earth, and contains tens of thousands of solar masses of gas and dust. The most prominent cluster of T Tauri stars and young B-type stars are in
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#17327721257701540-1053: Is considered to be the V-2 guidance system deployed by the Germans in 1942. However, inertial sensors are traced to the early 19th century. The advantages INSs led their use in aircraft, missiles, surface ships and submarines. For example, the U.S. Navy developed the Ships Inertial Navigation System (SINS) during the Polaris missile program to ensure a reliable and accurate navigation system to initial its missile guidance systems. Inertial navigation systems were in wide use until satellite navigation systems (GPS) became available. INSs are still in common use on submarines (since GPS reception or other fix sources are not possible while submerged) and long-range missiles. Not to be confused with satellite navigation, which depends upon satellites to function, space navigation refers to
1610-441: Is equivalent to 15 seconds of longitude error, which at the equator is a position error of .25 of a nautical mile, about the accuracy limit of manual celestial navigation. The spring-driven marine chronometer is a precision timepiece used aboard ship to provide accurate time for celestial observations. A chronometer differs from a spring-driven watch principally in that it contains a variable lever device to maintain even pressure on
1680-668: Is known to exist, preserved at the Colegio del Corpus Christi in Valencia, Spain . This copy is not easily accessible to visitors. Plancius also published journals and navigational guides and developed a new method for determining longitude . He also promoted the Mercator projection for navigational maps. Plancius was one of the founders of the Dutch East India Company , for which he drew over 100 maps. Plancius
1750-478: Is not affected by adverse weather conditions and it cannot be detected or jammed. Its disadvantage is that since the current position is calculated solely from previous positions and motion sensors, its errors are cumulative, increasing at a rate roughly proportional to the time since the initial position was input. Inertial navigation systems must therefore be frequently corrected with a location 'fix' from some other type of navigation system. The first inertial system
1820-453: Is particularly useful due to their high power and location near major cities. Decca , OMEGA , and LORAN-C are three similar hyperbolic navigation systems. Decca was a hyperbolic low frequency radio navigation system (also known as multilateration ) that was first deployed during World War II when the Allied forces needed a system which could be used to achieve accurate landings. As
1890-497: Is probably the earliest form of open-ocean navigation; it was based on memory and observation recorded on scientific instruments like the Marshall Islands Stick Charts of Ocean Swells . Early Pacific Polynesians used the motion of stars, weather, the position of certain wildlife species, or the size of waves to find the path from one island to another. Maritime navigation using scientific instruments such as
1960-459: Is reasonable for the navigator to simply monitor the progress of the ship along the chosen track, visually ensuring that the ship is proceeding as desired, checking the compass, sounder and other indicators only occasionally. If a pilot is aboard, as is often the case in the most restricted of waters, his judgement can generally be relied upon, further easing the workload. But should the ECDIS fail,
2030-692: Is sometimes also called the Frying Pan in Australia. Petrus Plancius Petrus Plancius ( Dutch: [ˈpeːtrʏs ˈplɑŋkijʏs] ; born Pieter Platevoet [ˈpitər ˈplaːtəvut] ; 1552 – 15 May 1622) was a Dutch - Flemish astronomer , cartographer and clergyman . Born, in Dranouter , now in Heuvelland , West Flanders , he studied theology in Germany and England. At
2100-564: The Age of Discovery . The earliest known description of how to make and use a sea astrolabe comes from Spanish cosmographer Martín Cortés de Albacar 's Arte de Navegar ( The Art of Navigation ) published in 1551, based on the principle of the archipendulum used in constructing the Egyptian pyramids . Open-seas navigation using the astrolabe and the compass started during the Age of Discovery in
2170-552: The United States in cooperation with six partner nations. OMEGA was developed by the United States Navy for military aviation users. It was approved for development in 1968 and promised a true worldwide oceanic coverage capability with only eight transmitters and the ability to achieve a four-mile (6 km) accuracy when fixing a position. Initially, the system was to be used for navigating nuclear bombers across
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2240-700: The mariner's astrolabe first occurred in the Mediterranean during the Middle Ages. Although land astrolabes were invented in the Hellenistic period and existed in classical antiquity and the Islamic Golden Age , the oldest record of a sea astrolabe is that of Spanish astronomer Ramon Llull dating from 1295. The perfecting of this navigation instrument is attributed to Portuguese navigators during early Portuguese discoveries in
2310-400: The "index mirror" is fixed to the top of the index arm, over the pivot. As the index arm is moved, this mirror rotates, and the graduated scale on the arc indicates the measured angle ("altitude"). The second mirror, referred to as the "horizon glass", is fixed to the front of the frame. One half of the horizon glass is silvered and the other half is clear. Light from the celestial body strikes
2380-405: The 15th and 16th centuries out of unfamiliar Southern Hemisphere stars. There are four bright stars in Chamaeleon that form a compact diamond-shape approximately 10 degrees from the south celestial pole and about 15 degrees south of Acrux , along the axis formed by Acrux and Gamma Crucis . Alpha Chamaeleontis is a white-hued star of magnitude 4.1, 63 light-years from Earth. Beta Chamaeleontis
2450-800: The 15th century. The Portuguese began systematically exploring the Atlantic coast of Africa from 1418, under the sponsorship of Prince Henry . In 1488 Bartolomeu Dias reached the Indian Ocean by this route. In 1492 the Spanish monarchs funded Christopher Columbus 's expedition to sail west to reach the Indies by crossing the Atlantic, which resulted in the Discovery of the Americas . In 1498,
2520-851: The Amsterdam cartographer Jodocus Hondius the Elder . The 12 new constellations (mostly referring to animals and subjects described in natural history books and travellers' journals of his day) are Apis the Bee (later changed to Musca by Lacaille ), Apus the Bird of Paradise, Chamaeleon , Dorado the Goldfish (or Swordfish), Grus the Crane, Hydrus the Small Water Snake, Indus the Indian, Pavo
2590-566: The Chamaeleon I cloud, and are associated with the reflection nebula IC 2631 . Chamaeleon contains one planetary nebula, NGC 3195 , which is fairly faint. It appears in a telescope at about the same apparent size as Jupiter . In Chinese astronomy , the stars that form Chamaeleon were classified as the Little Dipper ( 小斗 ; Xiǎodǒu ) among the Southern Asterisms ( 近南極星區 ; Jìnnánjíxīngōu ) by Xu Guangqi . Chamaeleon
2660-484: The Greenwich meridian to 180° east and west. Sydney , for example, has a longitude of about 151° east . New York City has a longitude of 74° west . For most of history, mariners struggled to determine longitude. Longitude can be calculated if the precise time of a sighting is known. Lacking that, one can use a sextant to take a lunar distance (also called the lunar observation , or "lunar" for short) that, with
2730-553: The North Pole to Russia. Later, it was found useful for submarines. Due to the success of the Global Positioning System the use of Omega declined during the 1990s, to a point where the cost of operating Omega could no longer be justified. Omega was terminated on September 30, 1997, and all stations ceased operation. LORAN is a terrestrial navigation system using low frequency radio transmitters that use
2800-682: The Peacock, Phoenix , Triangulum Australe the Southern Triangle, Tucana the Toucan, and Volans the Flying Fish. (The Southern Triangle and Southern Cross were reported as asterisms by earlier navigators and appear on earlier charts, but the globe of 1598 is the first surviving source that plots their locations reasonably accurately.) Also notable is the inclusion of Achernar as Alpha Eridani. These constellations, together with
2870-569: The Philippines, north to parallel 39°, and hit the eastward Kuroshio Current which took its galleon across the Pacific. He arrived in Acapulco on October 8, 1565. The term stems from the 1530s, from Latin navigationem (nom. navigatio ), from navigatus , pp. of navigare "to sail, sail over, go by sea, steer a ship," from navis "ship" and the root of agere "to drive". Roughly,
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2940-561: The age of 24 he became a minister in the Dutch Reformed Church . Plancius fled from Brussels to Amsterdam to avoid religious persecution by the Inquisition after the city fell into Spanish hands in 1585 . In Amsterdam he became interested in navigation and cartography and, having access to nautical charts recently brought from Portugal, he was soon recognized as an expert on safe maritime routes to India and
3010-495: The bridge wing for recording sight times. In practice, a wrist watch coordinated to the nearest second with the chronometer will be adequate. A stop watch, either spring wound or digital, may also be used for celestial observations. In this case, the watch is started at a known GMT by chronometer, and the elapsed time of each sight added to this to obtain GMT of the sight. All chronometers and watches should be checked regularly with
3080-421: The civilian navigator on a merchant ship or leisure craft must often take and plot their position themselves, typically with the aid of electronic position fixing. While the military navigator will have a bearing book and someone to record entries for each fix, the civilian navigator will simply pilot the bearings on the chart as they are taken and not record them at all. If the ship is equipped with an ECDIS , it
3150-518: The constellation Columba illustrated by Plancius on his large wall map of the world of 1592, were then incorporated in 1603 by Johann Bayer in his sky atlas, the Uranometria . In 1612 (or 1613) Plancius introduced the following eight constellations on a 26.5-cm celestial globe published in Amsterdam by Pieter van der Keere : Apes the Bee, Camelopardalis the Giraffe (often interpreted as
3220-667: The former's death in the Philippines in 1521. The fleet of seven ships sailed from Sanlúcar de Barrameda in Southern Spain in 1519, crossed the Atlantic Ocean and after several stopovers rounded the southern tip of South America . Some ships were lost, but the remaining fleet continued across the Pacific making a number of discoveries including Guam and the Philippines. By then, only two galleons were left from
3290-426: The horizon or more preferably a star, each time the sextant is used. The practice of taking celestial observations from the deck of a rolling ship, often through cloud cover and with a hazy horizon, is by far the most challenging part of celestial navigation. Inertial navigation system (INS) is a dead reckoning type of navigation system that computes its position based on motion sensors. Before actually navigating,
3360-480: The index mirror and is reflected to the silvered portion of the horizon glass, then back to the observer's eye through the telescope. The observer manipulates the index arm so the reflected image of the body in the horizon glass is just resting on the visual horizon, seen through the clear side of the horizon glass. Adjustment of the sextant consists of checking and aligning all the optical elements to eliminate "index correction". Index correction should be checked, using
3430-669: The initial latitude and longitude and the INS's physical orientation relative to the Earth (e.g., north and level) are established. After alignment, an INS receives impulses from motion detectors that measure (a) the acceleration along three axes (accelerometers), and (b) rate of rotation about three orthogonal axes (gyroscopes). These enable an INS to continually and accurately calculate its current latitude and longitude (and often velocity). Advantages over other navigation systems are that, once aligned, an INS does not require outside information. An INS
3500-705: The latitude of a place on Earth is its angular distance north or south of the equator . Latitude is usually expressed in degrees (marked with °) ranging from 0° at the Equator to 90° at the North and South poles. The latitude of the North Pole is 90° N, and the latitude of the South Pole is 90° S. Mariners calculated latitude in the Northern Hemisphere by sighting the pole star ( Polaris ) with
3570-448: The mainspring, and a special balance designed to compensate for temperature variations. A spring-driven chronometer is set approximately to Greenwich mean time (GMT) and is not reset until the instrument is overhauled and cleaned, usually at three-year intervals. The difference between GMT and chronometer time is carefully determined and applied as a correction to all chronometer readings. Spring-driven chronometers must be wound at about
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#17327721257703640-544: The navigation of spacecraft themselves. This has historically been achieved (during the Apollo program ) via a navigational computer , an Inertial navigation system, and via celestial inputs entered by astronauts which were recorded by sextant and telescope. Space rated navigational computers, like those found on Apollo and later missions, are designed to be hardened against possible data corruption from radiation. Another possibility that has been explored for deep space navigation
3710-462: The navigator will have to rely on his skill in the manual and time-tested procedures. Celestial navigation systems are based on observation of the positions of the Sun , Moon , planets and navigational stars . Such systems are in use as well for terrestrial navigating as for interstellar navigating. By knowing which point on the rotating Earth a celestial object is above and measuring its height above
3780-521: The navigator's position compared to known locations or patterns. Navigation, in a broader sense, can refer to any skill or study that involves the determination of position and direction . In this sense, navigation includes orienteering and pedestrian navigation. In the European medieval period, navigation was considered part of the set of seven mechanical arts , none of which were used for long voyages across open ocean. Polynesian navigation
3850-621: The nearby "spice islands". This enabled colonies and port trade in both, including what would become the Dutch East Indies , named after the Dutch East India Company set up in 1602. He saw strong potential in the little-mapped Arctic Sea and strongly believed in the idea of a Northeast Passage until the failure of Willem Barentsz 's third voyage in 1597 seemed to preclude its viability. In 1592 Plancius published his best known world map, titled "Nova et exacta Terrarum Orbis Tabula geographica ac hydrographica". Only one remaining copy
3920-405: The observer's horizon, the navigator can determine his distance from that subpoint. A nautical almanac and a marine chronometer are used to compute the subpoint on Earth a celestial body is over, and a sextant is used to measure the body's angular height above the horizon. That height can then be used to compute distance from the subpoint to create a circular line of position. A navigator shoots
3990-661: The original seven. The Victoria led by Elcano sailed across the Indian Ocean and north along the coast of Africa, to finally arrive in Spain in 1522, three years after its departure. The Trinidad sailed east from the Philippines, trying to find a maritime path back to the Americas , but was unsuccessful. The eastward route across the Pacific, also known as the tornaviaje (return trip) was only discovered forty years later, when Spanish cosmographer Andrés de Urdaneta sailed from
4060-476: The path a radar object should follow on the radar display if the ship stays on its planned course. During the transit, the navigator can check that the ship is on track by checking that the pip lies on the drawn line. Global Navigation Satellite System or GNSS is the term for satellite navigation systems that provide positioning with global coverage. A GNSS allow small electronic receivers to determine their location ( longitude , latitude , and altitude ) within
4130-429: The radar scanner. When a vessel (ship or boat) is within radar range of land or fixed objects (such as special radar aids to navigation and navigation marks) the navigator can take distances and angular bearings to charted objects and use these to establish arcs of position and lines of position on a chart. A fix consisting of only radar information is called a radar fix. Types of radar fixes include "range and bearing to
4200-517: The rear section of the fuselage, whereas most US aircraft enclosed the antenna in a small teardrop-shaped fairing. In navigational applications, RDF signals are provided in the form of radio beacons , the radio version of a lighthouse . The signal is typically a simple AM broadcast of a morse code series of letters, which the RDF can tune in to see if the beacon is "on the air". Most modern detectors can also tune in any commercial radio stations, which
4270-409: The same frequency range, called CHAYKA . LORAN use is in steep decline, with GPS being the primary replacement. However, there are attempts to enhance and re-popularize LORAN. LORAN signals are less susceptible to interference and can penetrate better into foliage and buildings than GPS signals. Radar is an effective aid to navigation because it provides ranges and bearings to objects within range of
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#17327721257704340-412: The same time each day. Quartz crystal marine chronometers have replaced spring-driven chronometers aboard many ships because of their greater accuracy. They are maintained on GMT directly from radio time signals. This eliminates chronometer error and watch error corrections. Should the second hand be in error by a readable amount, it can be reset electrically. The basic element for time generation
4410-400: The screen that is parallel to the ship's course, but offset to the left or right by some distance. This parallel line allows the navigator to maintain a given distance away from hazards . The line on the radar screen is set to a specific distance and angle, then the ship's position relative to the parallel line is observed. This can provide an immediate reference to the navigator as to whether
4480-511: The ship is on or off its intended course for navigation. Other techniques that are less used in general navigation have been developed for special situations. One, known as the "contour method," involves marking a transparent plastic template on the radar screen and moving it to the chart to fix a position. Another special technique, known as the Franklin Continuous Radar Plot Technique, involves drawing
4550-491: The southern sky. Keyser died in Java the following year – the expedition had many casualties – but his catalogue of 135 stars, probably developed with the help of Keyser's colleague Frederick de Houtman , was delivered to Plancius when the remaining ships returned. These stars appear as 12 new southern constellations , on a 35-cm celestial globe designed by Plancius in late 1597 (or early 1598) and produced in collaboration with
4620-537: The sparse information available about southern celestial features, depicted Crux (the southern cross), Triangulum Australe (the southern triangle), and the Magellanic Clouds ( Nubecula Major and Minor ). In 1595 Plancius trained Pieter Dirkszoon Keyser , the chief pilot on the Hollandia , to make astronomical observations to fill in the blank area around the south celestial pole on European maps of
4690-809: The table. The practice of navigation usually involves a combination of these different methods. By mental navigation checks, a pilot or a navigator estimates tracks, distances, and altitudes which will then help the pilot avoid gross navigation errors. Piloting (also called pilotage) involves navigating an aircraft by visual reference to landmarks, or a water vessel in restricted waters and fixing its position as precisely as possible at frequent intervals. More so than in other phases of navigation, proper preparation and attention to detail are important. Procedures vary from vessel to vessel, and between military, commercial, and private vessels. As pilotage takes place in shallow waters , it typically involves following courses to ensure sufficient under keel clearance , ensuring
4760-462: The time interval between radio signals received from three or more stations to determine the position of a ship or aircraft. The current version of LORAN in common use is LORAN-C, which operates in the low frequency portion of the EM spectrum from 90 to 110 kHz . Many nations are users of the system, including the United States , Japan , and several European countries. Russia uses a nearly exact system in
4830-548: Was closely acquainted with Henry Hudson , an explorer of the New World . Plancius prepared the map, Exacta & accurata delinatio… regionibus China, Cauchinchina, Camboja, sive Champa, Syao, Malacca, Arracan & Pegu, published in Jan Huygen van Linschoten 's popular book, Itinerario (1596). In 1589 Plancius collaborated with the Amsterdam cartographer Jacob van Langren on a 32.5-cm celestial globe, which, using
4900-438: Was the case with Loran C , its primary use was for ship navigation in coastal waters. Fishing vessels were major post-war users, but it was also used on aircraft, including a very early (1949) application of moving-map displays. The system was deployed in the North Sea and was used by helicopters operating to oil platforms . The OMEGA Navigation System was the first truly global radio navigation system for aircraft, operated by
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