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Navigation
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Air Almanac | The Air Almanac provides astronomical data for air navigation. The tables in the Air Almanac allow the navigator to convert astronomical sightings to a position given in degrees of Longitude and Latitude. |
Artificial horizon | Artificial horizon is an instrument that displays a line that lies within the horizontal plane and is not affected by the pitching, rolling and banking movements of an aircraft or sailing vessel. An artificial horizon can also be used when the true horizon is not visible due to fog, hills, trees or any obstruction. Lewis and Clark carried an "Artificial Horizon" that contained a pool of mercury or water covered by a sheet of glass. Since liquid will lie perfectly flat they could use the surface to find the true horizon. See Attitude indicator. |
Astrolabe | The astrolabe is a historical astronomical instrument used by astronomers, navigators and astrologers before the invention of the sextant in the 18th century. Its many uses included locating and predicting the positions of the Sun, Moon, planets and stars; determining local time given local longitude and vice-versa, surveying, and triangulation. |
Chip log | A chip log consists of a piece of wood, most often cut in the shape of a quarter circle, or "quadrangle", with a length of line (rope) attached to a spool and a knot tied in the line every 47 feet and 3 inches. The chip log would be placed into the water off the stern of the ship, the line would be allowed to be "paid out" (run out), and the number of knots paid out in 30 seconds counted. A sandglass was used to count the 30 seconds. A ship traveling at a speed of 1 knot in 30 seconds would travel 1 nautical mile per hour. This is the reason that ship measure their speed in knots. |
Chronometer | A chronometer is a very accurate, portable timekeeper device precise enough to be used as a time standard. John Harrison developed the first successful chronometers, which for the first time allowed a navigator to accurately assess his ship's position in longitude |
Compass | A compass consists of a magnetized pointer that is free to align itself accurately with Earth's magnetic field. An early form of the compass was invented in China in about 271 AD. The familiar mariner's compass was invented in Europe around 1300. The cardinal points are normally marked on the compass and are north, south, east and west. A compass can also be marked off in degrees, with north at 0°, east at 90°, south at 180° and west being at 270° and on to 360° at due north once again. The compass greatly improved maritime trade by making travel safer and more efficient. When the compass is used in conjunction with a chronometer and a sextant it can provide a very accurate means of navigation, |
Dividers | A divider is a tool used in navigation for measuring distances on the chart. A divider is usually made of metal, and consists of two parts connected by a hinge which can be adjusted. Each part of the compass ends with a spike. The separation between the two legs can be set using the scale located on the chart (map). The navigator then counts how many times the divider fits between two points on the chart. Also see Compass (drafting). |
Gyrocompass | The gyrocompass or gyroscopic compass was introduced in 1907 by inventor Elmer A. Sperry. The movement of the compass depends on a gyroscope, a free-spinning disk mounted on a base, so that the disk remains in a fixed position no matter what direction the base is moved. The gyroscope is aligned on a north-south axis, and the compass points to true north rather than magnetic north. This made the compass a more reliable navigational device, and Sperry's gyroscopic compass was adopted by the U.S. Navy in 1911, playing a major role in the First World War.[4] |
Gyroscope | A Gyroscope is a device with a rapidly spinning wheel on an axle that tends to resist changes to its orientation due to the angular momentum of the wheel. The gyroscope is a device for measuring or maintaining orientation, and is based on the principle of conservation of angular momentum. A gyroscope is the heart of the gyrocompass. |
Octant | The term "octant" means 1/8 of a circle, or 45 degrees. An Octant is an instrument based on the same principle as the sextant but employing only a 45° angle. |
Parallel rulers | A Parallel ruler consists of two straight edges joined by two arms which allow them to move closer or further away while always remaining parallel to each other. Parallel rules are used by the navigator to find bearing and direction and to draw parallel lines on a chart. |
Sandglass | A sandglass is a device for measuring time, (See Hourglass.) The invention of the chronometer made the sandglass obsolete for navigational purposes. |
Sextant | A sextant is used to measure the angle of elevation of a celestial object above the horizon. The sextant is used to determine latitude. This is done by measuring the angle between the horizon and the sun when the sun is at its highest point, then using tables to determine which line of latitude the sun should be above on that particular day. |
Sounding line | A sounding line or lead line is a length of thin rope with a weight at one end and with knots at a fixed interval along its length and is used to measure the depth of the water. The knots where normally tied every 1.8 meters (2 yards) or at 1 fathom intervals. The bottom of the weight was often hollow so that when the weight hit the sea floor a sample of the sediment was returned to the ship when the sounding line was hauled back aboard ship. When sounding lines were in common use, the nautical charts contained a description of the type of sediment at a particular death. This help to determine the exact position of a ship when it was close to shore. |
Theodolite | A Theodolite is an instrument for measuring both horizontal and vertical angles, as used in triangulation networks. It is a key tool in surveying, engineering work and cartography, but theodolites have been adapted for other specialized purposes in fields like meteorology and rocket launch technology. A theodolite consists of a telescope mounted movably within two perpendicular axes, the horizontal or trunnion axis, and the vertical axis. When the telescope is pointed at a desired object, the angle of each of these axes can be measured with great precision, typically on the scale of arc-seconds (Also see Minute of arc; Cartography). Jesse Ramsden provided a new large theodolite, known as the Ramsden theodolite, for General William Roy, of the Royal Engineers, which was used for a new survey of the distance between Greenwich, London and Paris in 1791. This work provided the basis for the subsequent Ordnance Survey of Britain. William Roy received the Copley Medal in 1795 for his survey of the United Kingdom and Ramsden, was elected to the Royal Society in 1786 for his important contributions to fields such as optics (the Ramsden eyepiece and electrostatics. |
For more information about Navigation Tool's, visit the following sites:
- NOAA - Marine Navigation
- Weems & Plath - The Grand Old Man of Navigation
- Navigation Tools from SailGB
- Navigation Tools used by Lewis and Clark
- Sailing Terminology
- How to use parallel rulers
- The Speed Log -- History, Construction and Use
- Elmer Ambrose Sperry - The Gyroscopic Compass
- Canadian Geographic - Finding Our Way
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Aids to Navigation
Today we have many aids to navigation. The type of navigational aid needed depends on whether you are on land, the water or in the air. Listed below are some of the many navigational aids in use today and a few historical ones.
Index of Aids to Navigation.
- Aids to Navigation - Land
- Aids to Navigation - Water
- Aids to Navigation - Air
- Aids to Navigation - Other
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Road signs - there are many different type of signs located along our roads that aid us in our trips to new places. Below are a few of the more familiar.
- Cardinal Direction Auxiliaries - normally located on highways that connect distant cities and town. These signs indicate the direction of travel, North, South, East or West.
- Destination, Distance, and General Guide Signs - these signs tell us what direction a location is (to the right, left or straight ahead) and how far we are from a place, normally the next city or town.
- Milestones - series of numbered markers placed along a road at regular intervals allow the traveler to know that the proper path is being followed and to indicate distance traveled, or the remaining distance to the desired destination. Today Milestone or markers are made of metal, but were originally stone (granite or marble or whatever local stone was available) obelisks. Milestones were used by the Roman Empire road builders on the Roman road network.
- Junction Signs - Indicates that two or more highways are crossing.
- Route Markers - Indicates the name or the number of the highway, examples are US 1 or Interstate 20.
- Street numbers (address) - the number assigned to the specific location such as a house of building. At a given location, there may be secondary address numbers such as an apartment number, suite, units or slip.
- Street signs - give the name of the street. These signs are normally located at the intersection of two or more streets.
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Trail Signs - the type of signs used to mark trails depends on the purpose (temporary or permanent) and the type of material (wood, grass, stones) available along the route of the trail.
- Cairns (Stone Signs) - Cairns are stones placed along trails that cross rocky areas where there are no trees or plants to mark the trail. A cairns may be stones stacked on top of another or laid out as a arrow pointing in the direction of travel.
- Grass and Twig Signs - These types of trail signs are left along a route by someone scouting ahead of a group and normally are less permanent than a blaze or a stone cairns.
- Blazes - these are marks normally made on a tree, but can also be left on large rocks when there are no trees. Originally, blazes were made by removing a section of bark from a tree with a knife or axe. Today, blazes are made using paint.
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- Benchmarks, survey marker and Geodetic control points are permanently affixed objects at various locations all over the United States to enable land surveying, civil engineering and mapping to be done efficiently. These objects are usually metal disks, but can be any other object that serves as a control point. The British mainland, and many of its off shore islands, have a abundance of small, roughly 4 foot high concrete called Trig Pillarsa. There are two general types of these control points; vertical control points and horizontal control points.
- Vertical control points are a series of points on which precise heights, or elevations, have been established. Vertical control stations are typically called benchmarks. This type of control point is usually, but not always, a small brass or aluminum disk, concrete post, iron pin, or bolt, (among other things), that is permanently attached to a stable foundation.
- A horizontal control point is for horizontal control and provide positional information (latitude and longitude). There are several names for horizontal control points, triangulation, traverse stations, trilateration stations, GPS stations, and intersection stations, depending on which kind of horizontal control system was used in establishing them and the amount of precision they represent. This type of control point can be a small brass or aluminum disk, concrete post, iron pin, or bolt, (similar to the vertical control points) but also be water towers, church spires, radio towers and mountain tops or any type of object that can be identified from a distance.
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- The British mainland, and many of its off shore islands, have a abundance of small, roughly 4 foot high concrete called Trig Pillars (horizontal control points). Each has a unique number, and were used to map Great Britain by 'triangulation' using a theodolite.
For more information about the Land Aids to Navigation, visit the following sites:
- The Manual of Traffic Signs
- Wikipedia - Traffic sign
- Wikipedia - Trail blazing
- Wikipedia - Survey marker
- Wikipedia - Milestone
- Trail Signs: Blazes
- Trail Signs: Traditional
- Trail Signs of Direction by Daniel Beard
- Using Signs to Reduce Visitor-Built Cairns: Gorham Mountain Trail
- Benchmarking - Images of Benchmarks and Related Objects
- National Geodetic Survey (NGS)
- Wisconsin Sate Castigator's Office - Introduction to Surveying
- About Space & Astronomy - geodetic control network
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Channel markers - markers placed in harbors, lakes or other waterways to aid in navigation.
- Buoy - A buoy is a floating device that can have many different purposes, which determines whether the buoy is anchored (stationary) or allowed to drift. Buoys used to mark channels are painted red and green and are always anchored. Generally speaking, green channel markers are kept to the RIGHT when leaving a harbor and red channel markers are kept to the RIGHT when returning to harbor, thus coining the phrase, "Red, Right, Returning". A buoy may also have a light to mark the position of the channel at night or have a bell to indicate the position of the buoy in bad weather.
- Preferred channel markers - are a combination of red and green markers that indicate the preferred channel. Years ago, this marker was known as a junction marker. The preferred or better channel is usually marked by having the top color of the marker indicate the way it should be treated.
- Range Day markers - are found in pairs with one higher than the other. Range markers indicate the center line of a channel by having them lined up as you pass through the channel. They will have vertical colored panels to assist in lining them up.
- Decca Navigator System was a hyperbolic low frequency radio navigation system (also known as multilateration) that was first deployed during World War II.
- Lighthouses are a building or framework sending out light from a system of lamps and lenses that are used to mark dangerous coastlines, hazardous shoals away from the coast, and safe entries to harbors. Since the higher the light is above the surface of the water, the further out to sea it is visible, lighthouses are normally very tall structures or are build high up on a cliff. Augustin-Jean Fresnel developed a design using lenses of large aperture and short focal length that concentrated the light and made it visible at a greater distance. The first Fresnel lens was used in 1822 in a lighthouse on the Gironde River in France, and could be seen from more than 20 miles out. The lens of the lighthouse would rotate so that rather than seeing a continuous weak light, a brighter light would be seen during a short time interval. Each lighthouse has a characteristic light pattern so lighthouses could be distinguished from each other. Lighthouses where are also painted with distinctive patterns so the navigator could distinguish which lighthouse was in sight during the day.
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- LORAN is an acronym for LOng RAnge Navigation. LORAN is a terrestrial based radio navigation system using low frequency radio transmitters that use the time interval between radio signals received from three or more stations to determine the position of a ship or aircraft. With the development of GPS, the use of LORAN is in steep decline.
For more information about the Marine Aids to Navigation, visit the following sites:
- USCG - Lighthouses, Lightships, Tenders & Other Aids to Navigation
- USCG - Navigation Center
- USCG - General Information on GPS
- Buoy Identification - Aids to Marine Navigation
- Wikipedia - Survey ship
- Attitude indicator or artificial horizon indicates an aircraft's orientation relative to the ground. It indicates pitch (fore and aft tilt) and roll (side to side tilt).
- Automatic Direction Finding (ADF) uses a series of non-directional beacons (NDF) located at a ground station and its associated automatic direction finding (ADF) equipment located in an aircraft. ADF is primarily a short distance navigational aid. The ground station (NDB) radiates a signal in all directions around the transmitter, and the aircraft receiver (ADF), when tuned to this signal, determines the direction from which the signal is being radiated. By following the direction indicated by the ADF instrument the aircraft will fly over the NDB.
- Heading indicator (HI), or the directional gyro, informs the pilot of his heading, or direction.
- OMEGA Navigation system was the first truly global radio navigation system for aircraft, operated by the United States in cooperation with six partner nations. Each Omega station transmitted a very low frequency signal (VLF)which consisted of a pattern of four tones unique to the station that was repeated every ten seconds. Because of this and radio-navigation principles, an accurate fix of the receiver's position could be calculated. OMEGA employed hyperbolic radio-navigation techniques and the chain of OMEGA stations operated in the VLF portion of the spectrum between 10 to 14 kHz.
- Instrument Landing System (ILS) is a system which provides precise guidance to an aircraft approaching a runway.
- VHF Omni Directional Range (VOR), is a type of radio navigation system for aircraft. VORs broadcast a VHF radio composite signal including the identification code (in Morse or voice), and data that allows the airborne receiving equipment to derive the magnetic bearing from the station to the aircraft. This line of position is called the "radial". The intersection of two radials from different VOR stations on a chart allows for a "fix" or specific position of the aircraft to be determined.
For more information about the Aviation Aids to Navigation, visit the following sites:
- Wikipedia - Air navigation
- Wikipedia - Wide Area Augmentation System (WAAS)
- Wikipedia - Instrument approach
- Wikipedia - Instrument meteorological conditions
- Wikipedia - Altimeter
- Wikipedia - Ground Speed
- Wikipedia - Air Speed
- Wikipedia - General James Harold Doolittle, Sc.D. USAF
- James H. "Jimmie" Doolittle -- Outstanding Man of Aviation
- On the Beam - ADF History
- Operational Notes on NDB & Associated Automatic Direction Finding (ADF)
- VOR (VHF Omni-Range)
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- Global Navigation Satellite System (GNSS) is the standard generic term for satellite navigation systems that provide autonomous geospatial positioning anywhere on the Earth.
- Global Positioning System (GPS) is a Global Navigation Satellite System (GNSS) consisting of more than two dozen GPS satellites located in medium Earth orbit (MEO). The GPS satellites transmit a signal that allows a GPS receiver to determine the receiver's location, speed and direction. A GPS receiver calculates its position by measuring the distance between itself and three or more GPS satellites.
- Radio direction finder is a device for finding the direction to a radio source. Because radio waves can travel very long distances "over the horizon", it makes a particularly good navigation system for ships and aircraft that are at a distance from land.
- GLONASS is a radio satellite navigation system created by the former Soviet Union, now Russia. It is the Russian counterpart to the United States GPS system
For more information about some of the other Aids to Navigation, visit the following sites:
- Wikipedia - European Union's Galileo Global Navigation Satellite System
- Wikipedia - Russian's GLONASS Global Navigation Satellite System
- Wikipedia - China's Beidou Global Navigation Satellite System
- Wikipedia - Huff-Duff
- Global Positioning System Overview by Peter H. Dana
- Trimble - GPS Tutorial
- Homing In - All About Radio Direction Finding (RDF)
- Radio Direction Finding Projects
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Maps
Index of Maps.
The study and practice of making maps or globes is known asCartography (in Greek chartis = map and graphein = write). Maps were traditionally made using pen and paper, and then with the invention of the airplane and the camera, a process called Photoimage mapping was developed. With the advent and spread of computers, cartography has been revolutionized. Today most commercial-quality maps are made with map-making software that falls into one of three main types; Computer-aided design (CAD), Geographic information system (GIS), and specialized map illustration software.
The cartographic process rests on the premise that the world is measurable and that we can make reliable representations or models of that reality. Mapmaking involves advanced skills and aptitudes in the use of symbols to represent certain geographic and physical phenomena. The Cartographer must be able to visualize the world in an abstract and scaled-down form.
Maps function as visualization tools for spatial data that is acquired from measurement and can be stored in various forms and then is used for a variety of purposes. Current trends in this field are moving away from analog methods of mapmaking and toward the creation of increasingly dynamic, interactive maps that can be manipulated digitally.
Several different map making traditions evolved between the 7th century and the 15th century. Most notably in the three major geographical areas of: Europe, the Middle East and Asia, each with its own traditions of expressing spatial concepts in graphic form.
The shape of the Earth is very close to an oblate spheroid (a rounded shape with a bulge around the equator) and is most easy represented as a globe. Flat maps can be more useful than globes in many situations. A map is more compact and easier to store, maps can more readily accommodate an enormous range of scales, they can facilitate measuring properties of the terrain, they are viewed easily on a flat computer displays, and they are cheaper to produce and transport. Cartographers use a technique called "projection" to show the round earth on a flat map.
A map projection is any method used in cartography (mapmaking) to represent the three-dimensional curved surface of the earth or other body on a two-dimensional plane. The term "projection" here refers to any function defined on the earth's surface and with values on the plane, and not necessarily a geometric projection.
Types of cartographical projects of the world:[5]
- Alberts Conic Equal-Area is a good format for mapping the mid-latitudes such as the United States. Lines of latitude on this type of project will appear to be curved.
- Azimuthal Equidistant is a project in which all distances measured from the center of the map along any longitudinal line are accurate. A useful application for this type of projection is a Polar Projection.
- Bottomley projection is an equal-area map projection. The lines of latitude are concentric elliptical arcs of constant eccentricity, centered on the North Pole. On the central meridian, shapes are not distorted, but elsewhere they are.
- Eckert Equal-Area projection was developed by German educator Max Eckert. Line poles for this project are half the length of the Equator. Polar regions are less compressed than on elliptical projections, low-latitude landmasses are elongated.
- Gnomonic projections displays all great circles as straight lines. On a Gnomonic projection the shortest route between two locations in reality corresponds to that on the map (see Great circle route). This is achieved by projecting, with respect to the center of the Earth (hence perpendicular to the surface), the Earth's surface onto a tangent plane. The least distortion occurs at the tangent point. Less than half of the sphere can be projected onto a finite map. Also see Map projection - Gnomonic
- Interrupted Goode Homolasine - To minimize distortion of scale and shape, the Interrupted Goode Homolasine project interrupts the globe, its equal-area quality makes it suitable for mapping distributions of various kinds of information.
- Lambert Azimuthal Equal-Area - Distance from the tangent point on the map is proportional to straight-line distance through the earth. Distortion away from the center makes this projection a poor choice for world maps but useful for fairly circular regions, such as the moon or the polar regions.
- Mercator projection developed by Flemish geographer and cartographer Gerardus Mercator, in 1569. The Mercator projection is a cylindrical map projection that became the standard map projection for nautical purposes because of its ability to represent lines of constant true bearing or true course, as straight line segments.
- Moltweide - In 1805 Carl B. Molloweide, a German mathematician, devised this elliptical equal-area projection that represents relative sizes accurately but distorts shape edges. Many thematic maps in Atlases use the Mollweide projection.
- Oblique Flat Polar Quartic projection, first presented in 1949, produces axes oblique to each other. Unlike many conventional world projections that display the two Poles as lines, Poles appear as points with less distortion.
- Orthographic projection is designed to show earth as seen from a distant point in space. The Orthographic project is usually used to show the hemisphere. Landmasses along the edge are distorted in this type of project.
- Stereographic - is a mapping that projects each point on a sphere onto a tangent plane along a straight line from the antipode of the point of tangency. Like the orthographic, this projection was used in the second century B.C. by Hipparchus. It was one of the first to show the world as round. All points lie in true direction from the center, but outer areas are stretched.
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The foundation for our modern systems of navigation and cartography were developed by Ptolemy; a Greek mathematician, geographer, astronomer, and astrologer. He assigned coordinates to all the places and geographic features he knew, in a grid that spanned the globe in the second century. After the fall of the Roman Empire the scientific advances represented by Ptolemy were lost to Europe and where replaced by Christian doctrine. Most mapmakers discarded the spherical Earth for a flat, circular one to produce world maps known as "Mappa mundi". These pictorial maps, centered on the holy city of Jerusalem, portrayed Old Testament and classical historical and geographical lore. Alongside these religious inspired maps practical and functional maps existed to aid travelers and seafarers. These itinerary maps and portolan charts were drawn to scale and provided detailed information on distances and directions.
After the conquest of Egypt by Arab armies in the seventh century (reference the Muslim conquest of Egypt) Greek scientific works, including Ptolemy's Alamgest and Geography, were translated into Arabic. In about 1400 a Byzantine copy of these works was translated into Latin and carried to Italy. This, combined with the invention of the printing press by Johannes Gutenberg, sparked a revival in scientific cartography that spread throughout Europe, and eventually around the world. The voyages of discovery by Europeans spurred European mapmaking and map use. Protolan charts expanded beyond the Mediterranean. In the first half of the 16th century, mapmakers in Vienna and Germany (Nurnberg, Heidelberg and Freiberg) began elementary land surveys of northern Italy and central Germany.
During the 17th century, the Netherlands produced some of the worlds greatest mapmaker. Gerardus Mercator developed a new world projection which still is used for navigation (see Mercator projection) today. Other prominent Dutch Cartographers are, Abraham Ortelius, Jodocus Hondius, Willem Janszoon Blaeu, and his son Joan Blaeu. They devised and introduced the atlas as a physical object and popularized printed sea charts and wall maps.
In the late 17th and 18th centuries, the French Royal Academy of Sciences sponsored measurements of an "arc of meridian". This led to a more accurate determination of the dimensions and shape of the Earth, perfected methods for determining longitude, and initiated the triangulation of France (Histoire de la triangulation en France). The French were the first to conduct an official national land survey based on triangulation and to establish an official hydrographic office for marine surveying, the Depot des Cartes et Plans de la Marine. The resulting Carte Giomitrique de fa France, begun in 1747, was completed 40 years later. It consisted of 182 sheets, with maps of uniform size and scale, 1:86,400.
Inspired by the French, other countries began large scale topographic surveys. In 1770 Belgium began the national land survey. Great Britain established its Ordnance Survey in 1784, and the British Hydrographic Office in 1795. By the late 19th century, official large-scale topographic map series had been prepared for most of Europe. The United States began geodetic surveys later than most of the world's major countries. The agency known as the Survey of the Coast began work in 1807. The agency was later identified as the Coast Survey in 1836, renamed the Coast and Geodetic Survey in 1878 and since about 1970 the National Geodetic Survey, presently an office in the National Ocean Service a division of the National Oceanic & Atmospheric Administration (NOAA). For more information on NOAA and the National Ocean Service, visit the NOAA home page, click here or for information about the history of NOAA, click here).
British surveyors began the Great Trigonometrical Survey of India on April 10, 1802. When the survey was completed near the end of the 19th century, India was probably the best-mapped region in the world. Radhanath Sikdar, an Indian mathematician and surveyor from Bengal, was the first to identify Mount Everest as the world's highest peak in 1852, using trigonometric calculations based on measurements of "Peak XV" (as it was then known) made with theodolites from 150 miles (240 km) away in India. Measurement could not be made from closer due to a lack of access to Nepal.
The Dutch Topographic Service began mapping in the Netherlands East Indies (Indonesia) in the 1860s. The first official topographic maps of Cambodia, Laos, and Vietnam were prepared by the French Army's Topographic Bureau in 1886. Similarly, the Japanese Army mapped Manchuria in the 1930s.
Thematic maps, also called statistical maps, are special purpose maps that illustrate a particular subject or theme. Thematic maps were introduced in the 1600s, but their value was not recognized until the 19th century. With the emergence of the natural sciences such as geology and meteorology, and the collection of census data, beginning in the United States in 1790 and Great Britain in 1801, the necessary data was collected to produce many types of Thematic maps. The adaptation of lithography to map printing during the first decade of the 19th century, and the introduction of color printing in the 1840s, provided an inexpensive and versatile method for reproducing the tones, shadings, and colors required to illustrate the qualitative and quantitative data portrayed by thematic maps.
Mapmaking became more specialized, efficient and accurate with the development of Aerial Photography during World War I, and the related deployment in the 1920s of instruments of photogrammetry - the science of making reliable measurements by the use of photographs. These plotting instruments reduced the need for ground surveys and helped translate the information on aerial photographs into detailed maps.
Military units mapped much of the world during World War II and the subsequent Cold War with the aid of aerial photographic techniques, improved plotting instruments, and high-speed, multi-color offset printing presses. The last quarter of the 20th century has been characterized by continuous and rapid innovation in cartography. Remote sensing satellites, global positioning systems (GPS), high speed computers and lunar and extraterrestrial space probes record mappable data at a daily rate unimaginable before.
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There are many types of maps in production and use today. Listed below is a sample of some of them.
- Aeronautical chart is a map designed to assist in navigation of aircraft. Using these charts and other tools pilots are able to determine their position, best route to a destination, navigation aids along the way, alternative landing areas in case of an in-flight emergency, and other useful information such as important radio frequencies and airspace boundaries.
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Geologic maps show subsurface geological features. Type of Geologic maps are:
- Oil and gas investigation maps and charts
- Geologic quadrangle maps - bedrock, sub-surface, or engineering geology
- Coal investigation maps
- Hydrologic Maps - show hydrologic features such as lakes, rivers and streams. They can also show information about water located below the surface. They may include the volume of water in storage (saturated thickness), elevation of the water table, land surface elevation and irrigation system location.
- Linguistic map - show the geographic distribution of the speakers of a language.
- Nautical chart - is a graphic representation of a maritime area and adjacent coastal regions
- Pictorial map - Pictorial maps are a category of maps that also loosely includes illustrated maps, panoramic maps, bird's-eye view maps and Geopictorial maps.
- Political map - shows political boundaries such as countries and states.
- Road maps - A map of roads, and possibly other features, to aid in navigation
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Thematic map - also called a statistical or special purpose map - displays the spatial pattern of a theme or series of attributes. Thematic maps may include:
- Early Indian Tribes
- Potential Natural Vegetation
- Topographic maps show both natural and man-made features and quantitative representation of relief, usually using contour lines.
- Topographic-bathymetric maps - show elevations above and below the water surface
- Trail maps provide information useful to hikers and campers as they travel cross country along the many designated hiking trails. Some examples of trail maps are:
- Weather map - provides a view of weather elements over a specified geographical area at a specified time.
- The most common cartographic convention is that North is at the top of a map. This is far from universal, however.
- Portolan charts are oriented to the shores they describe.
- Medieval European T and O maps such as the Hereford Mappa Mundi were centered on Jerusalem with east at the top. Indeed, prior to the reintroduction of Ptolemy's Geography to Europe around 1400, there was no single convention in the West.
- In pointing out the arbitrariness of the "north is up" convention, some southern-hemisphere publishers (notably Australians) have published "upside-down" maps of the world.
- Route and channel maps have traditionally been oriented to the road or waterway they describe.
- Maps from non-Western traditions are oriented in a variety of ways.
- Old maps of Edo show the Japanese imperial palace as the "top", but also at the centre, of the map. Labels on the map are oriented in such a way that you cannot read them properly unless you put the imperial palace above your head.
- Buckminster Fuller's Dymaxion maps are based on a projection of the Earth's sphere onto an icosahedron. The resulting triangular pieces may be arranged in any order or orientation.
- Polar maps of the Arctic or Antarctic regions are conventionally centered on the pole, making "north is up" meaningless.
- Azimuthal or Gnomonic projections are often used in planning air routes, centered on specific origin points.
- Richard Edes Harrison produced a striking series of maps during and after World War II for Fortune magazine. These used "bird's eye" projections to emphasize globally strategic "fronts" in the air age, pointing out proximities and barriers not as apparent on a conventional rectangular projection of the world.
- Many but not all maps are drawn to a scale. An example of a map not drawn to scale is the London Underground map, which best fulfils its purpose by being less physically accurate and more visually communicative to the hurried glance of the commuter. Also see Tube Maps.
For more information about the Maps, visit the following sites:
- The Atlas of North America
- USGS - Maps
- USGC - The Universal Transverse Mercator (UTM) Grid
- USGS - Topographic Map Symbols
- USGC - Topography
- National Aeronautical Charting Office
- SkyVector.com - Online Aeronautical Charts
- NOAA - Office of Cost Survey
- The Universal Transverse Mercator System
- Digital Nautical Chart (DNC®)
- News - 21st-Century Maps Reflect Changing Technologies and Needs
- How To Read Topographical Maps
- Wikipedia - Maps
- Wikipedia - Topographic map
- Wikipedia - Map Projections
- Wikipedia - List of cartographers
- Wikipedia - Benchmark (surveying)
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Navigation Games
Games Using GPS Systems
Geocaching
Geocaching (pronounced "geocashing") is a game in which players hide objects that other players use Global Positioning System (GPS) receivers to find. Traditionally, the hidden object is a waterproof container with a log book and various inexpensive prizes. Finders are encouraged to take something, leave something, and sign the log.
Shutterspot
Shutterspot is a game in which some players take photographs and other players are challenged to find the exact spot where the photographer stood when the camera shutter clicked. That's the "Shutterspot".
Benchmark Hunting
Benchmark Hunting is similar to Geocaching but rather than searching for cashes hidden by others you search for Geodetic control points called benchmarks. Geodetic control points are permanently affixed objects at various locations all over the United States to enable land surveying, civil engineering and mapping to be done efficiently. These objects are usually metal disks, but can be any other object such as radio towers, water towers, church spires and mountain tops can all serve as a control point.
For more information on Benchmark Hunting, visit Papa Bear's Benchmark Hunting Site
Benchmark Hunting Wiki
Waymarking
Waymark is similar to Geocaching but rather than searching for cashes hidden by others you search everyday object that have been waymarked by others. There are waymarking categories different type of objects to find. An example is the category of "City and Town Halls". A City Hall is entered in to the database and then others visit, or if you are the first to visit, then you can enter the City Hall as a new waymark. It is similar to a scavenger hunt.
Games Using Map and Compass
Route Orienteering
In Route Orienteering you follow a route using a map and a compass. The rout is laid out by the organizers of the event. Parts of the rout may be along roads and part may be cross-country. The route is indicated on a master map located at the routs starting point; you copy off the route on your own map and follow the rout using your map and compass. There are a number of stations not marked on the map located at various points along the rout. The object is to mark the location of each of these stations on your map. The winner of the event is the participant who has found the most stations and has indicated them correctly on his map, Speed is not counted, but a time limit should be set.
Project Orienteering
Project Orienteering tests your map-and-compass skills and your other outdoor skills as well. As you follow; the route, laid out as for route orienteering, you arrive at various stations where signs tell you what to do. Projects may be anything from collecting from a number of different leaves or boiling a quart of water to deciphering a Morse code message or chopping through a log. The separate scores you receive from the judges located at the different project stations are added to your orienteering score.
Point Orienteering
In point orienteering you are not given a definite route but only the location of a number of points which you have to reach one after the other in numerical order. You select your own route from one point to the next, and decide on the quickest and easiest way of getting there. The organizers of the event may show you all the points on a master map so that you'll know all of them before setting out, but it is more common to have each point revealed one at a time on a marker at each station.
Score Orienteering
Score orienteering is a variation of point orienteering. The map is put up at the starting point with a number of stations marked on it. Next to each station mark is a figure which indicates the score you'll receive if you succeed in getting to that station. The nearby; easily reached stations have low point values; the faraway, tough to reach station have a higher point value. You have to layout your own route, planning it in such a way that you'll get the biggest possible score within the specified time limit.
Tracking
Tracking involves laying a trail or following a trail laid by others. A trail is a serial of trail signs, namely directions, laid on the ground.
For more information about the Navigation games, visit the following sites:
- Orienteering - reading a topographical map
- Types of Orienteering Events
- Sports History - Orienteering
- Wikipedia - Geocaching
- Wikipedia - Benchmarking (geolocating)
- Getting Started with Geocaching
- Geocaching with navicache.com
- Shutter Spot - cafepress.com
- Geocaching and Caches in Poland - 4x4 Off Road Adventure Club Poland
- Benchmark Hunting
- Wikipedia - Tracking
- Trail Descriptions & Trail Maps
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Navigators/Explorers/Surveyors
This is a list of some of the many navigators, explorers, cartographers and surveyors that helped to map our world. For a more complete list, visit list of explorers and the list of cartographers on Wikipedia. Also see Distinguished Women of Past and Present for information on women explores.
276 BC-194 BC | Eratosthenes |
Eratosthenes was a Greek mathematician who is famous for his work on prime numbers and for measuring the diameter of the earth.
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610 BC–546 BC | Anaximander |
Anaximander was a Greek philosopher and is often called the founder of astronomy. He was also the first to publish a map of the world.
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90–168 | Ptolemy |
Ptolemy was a Greek mathematician, geographer, astronomer, and astrologer. He assigned coordinates to all the places and geographic features he knew, in a grid that spanned the globe. Ptolemy figured out that lines of latitude had to be parallel to each other and that meridians (line of longitude) had to be arcs of a circles that came together at the poles.
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10th century | Bjarni Herjólfsson |
Bjarni Herjólfsson was a Norse explorer who is the first known European discoverer of the mainland of the Americas, which he sighted in 986.
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950 – 1000 | Eric the Red |
Eric the Red (950-1000) was from Norway and the founder of the first European settlement in Greenland.
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970 - 1020 | Leif Ericson | Leif Ericson (c. 970 - c. 1020) was a Norwegian navigator who, according to Norse sagas, was blown off course when voyaging to Greenland and thereby discovered and named Vinland, probably in Nova Scotia or New England. |
1254 - 1324 | Marco Polo |
Marco Polo (September 15, 1254 - January 8, 1324) was born in Venice Italy and traveled the "silk road" for 24 years. He traveled beyond Mongolia to China and became a confidant of Kublai Khan (1214-1294). He traveled the whole of China and returned to tell the tale.
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1450 - 1500 | Bartolomeu Dias |
Bartolomeu Dias (c. 1450 - May 29, 1500) was a Portuguese explorer that sailed around the Cape of Good Hope.
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1450 - 1499 |
John Cabot (Giovanni Caboto) |
John Cabot (c. 1450 - c.1499), was an Italian navigator and explorer commonly credited as one of the first early modern Europeans to discover the North American mainland, in 1497.
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1451 - 1506 | Christopher Columbus |
Christopher Columbus (1451 - May 20, 1506) was a navigator and maritime explorer born in Genoa, Italy. He sailed from Spain across the Atlantic Ocean in 1492, landing in the "new world" of the Americas and gaining lasting fame. While the Americas had already been "discovered" by other explorers before Columbus, his impact and significance in history has more to do with his time and its effects. His journey came when technical developments in sailing techniques and communication made it possible to report his voyages easily throughout Western Europe.
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1454 - 1512 | Amerigo Vespucci |
Amerigo Vespucci (March 9, 1454 - February 22, 1512) was an Italian merchant, explorer and cartographer. Vespucci explored the coast of South America and discovered the mouth of the Amazon River. He determined that the land masses he and Alonso de Ojeda had explored were much larger than anticipated and different from the Asia described by earlier Europeans and, therefore, must be a continent. The name "America" is from Vespucci's Latinized name "Americus".
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1460 - 1521 | Juan Ponce de Léon |
Juan Ponce de Léon (c. 1460 - July 1521) was a Spanish conquistador. He was born in Santervás de Campos (Valladolid), Spain. In 1508, Ponce de Léon founded the first settlement in Puerto Rico, Caparra. The Spanish Crown by then had selected Ponce de Léon to colonize and govern the island of Puerto Rico. He was removed from office by the Spanish crown in 1512. In 1513 he equipped three ships at his own expense, and set out on his voyage of discovery and conquest. On April 2 he landed on the northeast coast of the present State of Florida. He then sailed south along the Florida coast, charting the rivers he found, passed around the Florida Keys, and up the west coast of Florida to Cape Romano. From there he sailed back south to Havana, and then up to Florida again, stopping at the Bay of Chequesta (Biscayne Bay) before returning to Puerto Rico.
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1469 - 1524 | Vasco da Gama |
Dom Vasco da Gama (c. 1469 - December 24, 1524 ) was a Portuguese explorer. He was one of the most successful in the European Age of Discovery, and the commander of the first ships to sail directly from Europe to India.
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1475 - 1519 | Vasco Núñez de Balboa |
Vasco Núñez de Balboa (1475-January 15, 1519) was a Spanish explorer, governor, and conquistador. He traveled to the New World in 1500, and after some explorations settled on the island of Hispaniola. He was the first European to reach the eastern shore of the Pacific Ocean, on September 13, 1513.
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1480 - 1521 | Ferdinand Magellan |
Ferdinand Magellan (spring 1480-April 27, 1521) was born in Portugal and was a maritime explorer. He was employed by the Spanish to find a westward route to the Spice Islands of Indonesia. This voyage became known as the first successful attempt to circumnavigate the world. He was killed during the Battle of Mactan in the Philippines before completing his final westward voyage. He did, however, die farther west than the Spice Islands, which he had visited from the west on earlier voyages, making him one of the first individuals to cross all the meridians of the globe. He became the first person to lead an expedition sailing westward from Europe to Asia and to cross the Pacific Ocean. Magellan is also recognized as the first European explorer to enter the Pacific from the Strait of Magellan, which he discovered. |
1497 - 1542 | Hernando de Soto |
Hernando de Soto (c. 1496/1497-May 21, 1542) was a Spanish navigator and conquistador, born in the Extremadura region of Spain. Hernando de Soto led the largest expedition of both the 15th century and the 16th century through what would become the Southeastern United States and the Midwestern United States searching for gold and silver and other valuable goods. He is believed to have died on the banks of the Mississippi River near present-day Lake Village, Arkansas.
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1510 - 1554 | Francisco Vásquez de Coronado | Francisco Vásquez de Coronado (ca. 1510 - September 22, 1554) was a Spanish conquistador, who between 1540 and 1542 explored parts of the of what is now known as the southwestern United States. |
1512 - 1594 | Gerardus Mercator |
Gerardus Mercator (March 5, 1512 - December 2, 1594) was a Flemish cartographer who developed the Mercator projection. The Mercator projection is a cylindrical map projection that became the standard map projection for nautical purposes because of its ability to represent lines of constant true bearing or true course, as straight line segments.
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>1681 - 1741 | Vitus Bering |
Vitus Jonassen Bering (August 1681 - December 19, 1741) was a Danish-born navigator in the service of the Russian Navy and served in the Baltic Fleet during the Great Northern War. From his base in Okhotsk (59°22'N 143°15'E) he crossed to the Kamchatka Peninsula, and built the ship Sviatoi Gavriil (St. Gabriel). Aboard the ship, Bering pushed northward in 1728, until he could no longer observe any extension of the land to the north, or its appearance to the east. These voyages of Bering and Aleksei Chirikov were a major part of the Russian exploration efforts in the North Pacific known today as the Great Northern Expedition. He also explored the coast of Alaska and the Aleutian Islands. The Bering Strait, the Bering Sea, Bering Island, Bering Glacier and the Bering Land Bridge bear the explorer's name.
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1728 - 1779 | James Cook |
Captain James Cook (October 27, 1728 - February 14, 1779) was a British explorer, cartographer and navigator. Cook made three voyages to the Pacific Ocean. He mapped the complete coastline of New Zealand and was the first recorded European to have encountered the eastern coast of Australia. Cook circumnavigated the globe at a very high southern latitude, becoming one of the first to cross the Antarctic Circle. On his third voyage to the Pacific, he became the first European to sail to the Hawaiian Islands, he explored the west coast of North America, and mapped the coast from California all the way to the Bering Sea. Cook accurately charted many areas and recorded several islands and coastlines on European maps for the first time. He also mapped Newfoundland and confirmed many of the observation made by Vitus Bering.
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1732 - 1799 | George Washington | George Washington (February 22, 1732 - December 14, 1799) was born in the United States. He was a surveyor, general and first President of the United States. In his youth, Washington worked as a surveyor of rural lands and acquired what would become invaluable knowledge of the terrain around his native state of Virginia. |
1757 - 1798 | George Vancouver |
Captain George Vancouver (June 22, 1757 - May 12, 1798) was an officer of the Royal Navy. He explored North America, including the Pacific coast along the Canadian province of British Columbia and the present day U.S. states of Washington and Oregon. He also explored the southwest coast of Australia and negotiated agreements with Kamehameha I, king of the Kingdom of Hawaiʻi (Hawaiian Islands).
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1770–1838 | William Clark | William Clark (August 1, 1770 - September 1, 1838) was a Scottish-American explorer who accompanied Meriwether Lewis on the Lewis and Clark Expedition. Clark lead the "voyage of discovery " ordered by President Thomas Jefferson to "explore the Missouri river, and such principal stream of it as by its course and communication with the waters of the Pacific ocean whether the Columbia, Oregon, Colorado or any other river may offer the most direct and practicable water communication ". William Clark concentrated chiefly on the drawing of maps, the management of the expedition's supplies, and the identification of native plants and animals. Using Keelboats; the "Corps of Discovery" followed and mapped the Missouri river from St. Louis, Missouri to its headwaters, then crossed the Continental Divide at Lemhi Pass via horses. In canoes, they descended the mountains by the Clearwater River, the Snake River, and the Columbia River, past Celilo Falls and past what is now Portland, Oregon, to the Pacific Ocean. On the return trip, Lewis took one group north to explore the Marias River while Clark took the remainder of the group south. Clark's expedition went south to Gibbons Pass, then to Bozeman Pass. They eventually reached the Yellowstone River which they followed to the Missouri River where they rejoined the rest of the Corp.[6] |
1774 - 1809 | Meriwether Lewis | Captain Meriwether Lewis (August 18, 1774 - October 11, 1809) was an American explorer, soldier, and public administrator, who with William Clark led the Corps of Discovery, whose mission was to explore the territory of the Louisiana Purchase. The Lewis and Clark Expedition ordered by President Thomas Jefferson " to explore the Missouri river, and such principal stream of it as by its course and communication with the waters of the Pacific ocean whether the Columbia, Oregon, Colorado or any other river may offer the most direct and practicable water communication". Using Keelboats; the "Corps of Discovery" followed and mapped the Missouri river from St. Louis, Missouri to its headwaters, then crossed the Continental Divide at Lemhi Pass via horses. In canoes, they descended the mountains by the Clearwater River, the Snake River, and the Columbia River, past Celilo Falls and past what is now Portland, Oregon, to the Pacific Ocean. On the return trip, Lewis took one group north to explore the Marias River while Clark took the remainder of the group south. |
>1788 - 1852 | Fabian Gottlieb Thaddeus von Bellingshausen | Fabian Gottlieb von Bellingshausen (September 20, 1778 - January 13, 1852) served as a naval officer of the Russian Empire and commanded the second Russian expedition to circumnavigate the globe. During this expedition to the South Polar Region in 1819, Bellingshausen became one of three people to first see the continent of Antarctica. He attained the rank of admiral and became the military governor of Kronstadt (from 1839) and died there in 1852. The Bellingshausen Sea is an area along the west side of the Antarctic Peninsula which was named after him. |
1790 - 1866 | George Everest |
Colonel Sir George Everest (July 4, 1790 - December 1, 1866) was a Welsh surveyor, geographer and Surveyor-General of India from 1830 to 1843. It is a fitting tribute to the man who, for more than twenty-five years and despite numerous hardships, prevailed in surveying the longest are-of-the-meridian ever accomplished at the time that the highest mountain in the world as measured by the height of its summit above sea level, Mount Everest is named for him. The Great Trigonometric Survey of India, begun at Cape Comorin in 1806 by William Lambton and completed by Everest in 1843, would then run almost 1,492 miles north to the Himalayas. During this tremendous undertaking, Everest made countless adaptations to the surveying equipment, methods, and mathematics in order to minimize problems specific to the Great Survey immense size and scope, terrain, weather conditions, and his desired for accuracy.
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1834 - 1902 | John Wesley Powell |
John Wesley Powell (March 24, 1834 - September 23, 1902) was a U.S. soldier, geologist, and explorer of the American West. He led the 1869 Powell Geographic Expedition, a three-month river trip down the Green River and the Colorado River. The Powell expedition was the first to explore the Grand Canyon.
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1866 - 1955 | Matthew Alexander Henson |
Matthew Alexander Henson (August 8, 1866 - March 9, 1955) was an American explorer. Matthew Henson was part of Robert Peary's various expeditions. The most famous was a 1909 expedition which was probably the first to reach the Geographic North Pole
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1874 - 1922 | Ernest Henry Shackleton | Ernest Henry Shackleton (February 15, 1874 - January 5, 1922) was an Anglo-Irish explorer who made 5 trips to explore the Antarctic. His 3rd Antarctic expedition (1914-1916) was aboard the ship Endurance. The plan was to cross Antarctica via the South Pole. Early in 1915, Endurance became trapped in the ice, and ten months later sank. Shackleton's crew had already abandoned the ship to live on the floating ice. In April 1916, they set off in three small boats, eventually reaching Elephant Island. Taking five crew members, Shackleton went to find help. In a small boat, the six men spent 16 days crossing 1,300 km of ocean to reach South Georgia and then trekked across the island to a whaling station. The remaining men from the Endurance were rescued in August 1916. Incredibly, not one member of the expedition died. Shackleton's account of the Endurance expedition was published in 1919. Shackleton died of a heart attack on board his ship, the Quest, during his 5th trip to Antarctica. |
1884 - 1962 | Auguste Piccard |
Auguste Antoine Piccard (January 28, 1884 - March 24, 1962) was a Swiss physicist, inventor and explorer. His interest in ballooning, and a curiosity about the upper atmosphere led him to design a spherical, pressurized aluminum gondola which would allow ascent to great altitude without requiring a pressure suit. In 1931 he reached a record altitude of 51,775 ft. During this flight, Piccard was able to gather substantial data on the upper atmosphere, as well as measure cosmic rays. He later developed the deep diving submarine called a bathyscaphe.
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1888 – 1957 | Richard Evelyn Byrd | Rear Admiral Richard Evelyn Byrd, USN (October 25, 1888 - March 11, 1957) was a pioneering American polar explorer and famous aviator. In 1928, Byrd established a camp in Antarctica named "Little America" on the Ross Ice Shelf. Richard Byrd along with pilot Bernt Balchen, co-pilot/radioman Harold June, and photographer Ashley McKinley flew to the South Pole on November 29, 1929. |
1889 - 1979 | Philip Van Horn Weems |
Captain Philip Van Horn Weems, USN (1889 - June 2, 1979) was an American navigator who developed many tools and processes to simplify and automate the problems of navigation so that anyone with a high school education could master basic celestial navigation.
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1910 – 1997 | Jacques-Yves Cousteau |
Jacques-Yves Cousteau (11 June 1910 - 25 June 1997) was a French naval officer, explorer, ecologist, scientist, researcher, filmmaker and photographer who studied the oceans and all forms of life in the water. He co-developed the aqua-lung with Emile Gagnan. Cousteau and his team explored the world oceans and some rivers in the ex-Royal Navy minesweeper Calypso.
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1916 - 2000 | George W. Gibbs, Jr. |
George W. Gibbs, Jr. (Nov. 7, 1916 - Nov. 7, 2000) was an American explorer who accompanied Richard E. Byrd on his third Antarctic expedition.
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1930 - | Edwin (Buzz) Eugene Aldrin, Jr. | Colonel Buzz Eugene Aldrin, Sc.D (January 20, 1930 - ) is an American pilot and astronaut who was the Lunar Module Pilot on Apollo 11, the first lunar landing. He became the second man to set foot on the Moon on July 20, 1969. |
1930 - 2012 | Neil Armstrong | Neil Alden Armstrong (August 5, 1930 - August 25, 2012 ) is an American astronaut, test pilot, university professor, and Naval Aviator. He flew on Apollo 11 and was the first human to set foot on the Moon on July 20, 1969. |
1942 - | Guion Bluford, Jr. |
Guion (Guy) Bluford, Jr. (born November 22, 1942) is a NASA Astronaut. He participated in four flights of the Space Shuttle between 1983 and 1992. In 1983 he was a member of the crew of the space shuttle Challenger on mission STS-8.
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References
- ^ Wikipedia, Navigation. [Online] http://en.wikipedia.org/wiki/Navigation
- ^ Dickinson, Rachel Tools of Navigation. White River Junction, VT: Nomand Press, ©2005 pp 25-26
- ^ Ralph E. Ehrenberg Mapping the World; An Illustrated History of Cartography. National Geographic, Washington DC ©2006 p 23
- ^ Canadian Geographic Finding Our Way. [Online] http://www.canadiangeographic.ca/Magazine/ND01/findingourway.asp
- ^ National Geographic Atlas of the World seventh edition. Washington DC; National Geographic, ©2006 plate 3.
- ^ Ambrose, Stephen E. Undaunted Courage. Simon & Schuster, ©1996
- ^ Ralph E. Ehrenberg Mapping the World; An Illustrated History of Cartography. Washington DC; National Geographic, ©2006 pp 10-13.
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