The Mercator projection was originally developed in by the Flemish cartographer Gerardus Mercator. Although accurate, these projections were difficult for navigators and explorers to use because they required that bearing constantly be recalculated as they moved Stockton, Mercator found that to keep the rhumb lines straight he had to make lines of latitude move away from each other as they moved north and south of the equator.
Many discussions of how the Mercator projection works say to imagine a cylinder with a globe inside Stockton, The globe should have a light inside so that an image of the world is projected onto the cylinder.
Because the cylinder only touches the globe at the equator points along that parallel are the only ones on the projection that are completely accurate. Additionally, because the cylinder is perpendicular to the globe, lines of longitude are straight, instead of curved as on a globe when they are transferred to the cylinder. This meant that sailors using maps in that projection no longer had to recalculate their bearings on long journeys.
Instead they could mark their starting and ending points and simply follow the line along their expeditions. Due to this, the Mercator projection made world exploration much easier and became a essential map projection for navigation. Using a cylinder and a globe with light is a simplified explanation as to how the Mercator projection works.
In reality it is very complicated to derive the projection and it takes complex mathematical formulas to fully explain it Israel, Maps have been a part of the National Geographic Society since the beginning. Gilbert H. It's lines and colors show the realization of great dreams. A map is a symbolic representation of selected characteristics of a place, usually drawn on a flat surface. Students look at lines of latitude and longitude on United States and world maps, discuss why these lines are helpful, and identify landmarks with similar latitude and longitude.
Cartographers at National Geographic discuss how they select an appropriate map projection for the September issue. Join our community of educators and receive the latest information on National Geographic's resources for you and your students.
Skip to content. Image Mercator World Map Geradus Mercator's world maps flattened the spherical planet to make it easier to display. Twitter Facebook Pinterest Google Classroom.
Encyclopedic Entry Vocabulary. Media Credits The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. Media If a media asset is downloadable, a download button appears in the corner of the media viewer.
Text Text on this page is printable and can be used according to our Terms of Service. Interactives Any interactives on this page can only be played while you are visiting our website. Related Resources. The oldest known record of this projection is from Ptolemy in about AD. However it is believed that this projection was well known long before that time — probably as far back as the 2nd century BC.
Today, this is probably one of the most widely used Azimuthal projections. It is most commonly used over Polar areas, but can be used for small scale maps of continents such as Australia.
The great attraction of the projection is that the Earth appears as if viewed form space or a globe. This is a conformal projection in that shapes are well preserved over the map, although extreme distortions do occur towards the edge of the map. One interesting feature of the Stereographic projection is that any straight line which runs through the centre point is a Great Circle. The advantage of this is that for a place of interest e.
Canberra, the capital city of Australia a map which uses the Stereographic projection and is centred on that place of interest true distances can be calculated to other places of interest e. His mathematics was considered revolutionary for its time and is still considered important today. Today the Lambert Conformal Conic projection has become a standard projection for mapping large areas small scale in the mid-latitudes — such as USA, Europe and Australia.
It has also become particularly popular with aeronautical charts such as the , scale World Aeronautical Charts map series. This projection commonly used two Standard Parallels lines of latitudes which are unevenly spaced concentric circles.
The projection is conformal in that shapes are well preserved for a considerable extent near to the Standard Parallels. For world maps the shapes are extremely distorted away from Standard Parallels. Distances are only true along the Standard Parallels.
Across the whole map directions are generally true. One of the most famous map projections is the Mercator, created by a Flemish cartographer and geographer, Geradus Mercator in It became the standard map projection for nautical purposes because of its ability to represent lines of constant true direction. Constant true direction means that the straight line connecting any two points on the map is the same direction that a compass would show.
In an era of sailing ships and navigation based on direction only, this was a vitally important feature of this projection. Other projections have come in and out of vogue, but all of them have issues. There are many variations of the Mercator projection that try to twist the formula, with varying success. Alternative solutions like the Robinson projection fix some issues, but are still distorted at the poles. The Robinson Projection Wikimedia Commons.
The Gall-Peters projection , designed as a response to the Mercator projection's flaws, is also distorted near the poles. The Mercator Projection Wikimedia Commons. In an era of digital mapping, however, Mercator's work has reemerged thanks to its readability. Most sites and apps use the Web Mercator projection.
Mercator never could have anticipated being part of an app on your phone, but he probably would have recognized his map. Our mission has never been more vital than it is in this moment: to empower through understanding. Financial contributions from our readers are a critical part of supporting our resource-intensive work and help us keep our journalism free for all.
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By choosing I Accept , you consent to our use of cookies and other tracking technologies. Gerardus Mercator revolutionized mapmaking. He was almost executed for it. Reddit Pocket Flipboard Email. A portrait of Gerardus Mercator. Why Mercator's maps were such a huge deal Today we're so familiar with the Mercator projection that it's easy to forget how revolutionary it was at the time.
Wikimedia Commons His new map was a revelation, because the projection kept the latitude and longitude lines at consistent 90 degree angles.
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