What is WGS 1984 Web Mercator auxiliary sphere?
What is WGS 1984 Web Mercator auxiliary sphere?
WGS 1984 Web Mercator and WGS 1984 Web Mercator (Auxiliary Sphere) use a conformal projection that preserves direction and the shape of data but distorts distance and area. Published in 1569 by Gerardus Mercator, the Mercator projection was created for use in navigation.
What is a wgs84 Web Mercator coordinate system?
Web Mercator Coordinate System It is the de facto standard for web maps and online services. With this coordinate system, the geodetic coordinates defined on the WGS 84 datum are projected as if they were defined on a sphere, using a sphere-based version of the Mercator projection.
What is an auxiliary sphere?
Given a spheroid we may associate with it a sphere whose size is determined by some well- defined mathematical property of the spheroid. Such a sphere is called an auxiliary sphere [Deetz and Adams 1945].
What Epsg 3857?
EPSG:3857 is a Spherical Mercator projection coordinate system popularized by web services such as Google and later OpenStreetMap.
Why do we use WGS84?
WGS84: Unifying a Global Ellipsoid Model with GPS The radio waves transmitted by GPS satellites and trilateration enable extremely precise Earth measurements across continents and oceans. Geodesists could create global ellipsoid models because of the enhancement of computing capabilities and GPS technology.
Does Google Maps use WGS84?
Google Earth (also Google Maps and Microsoft Virtual Earth) use a Mercator projection based on a spherical datum (in ESRI parlance, datum = “Geographic Coordinate System; GCS”) that is a modification of the WGS84 datum.
Why does Google use Mercator?
A Google employee explained in 2009 that the company used a Mercator map because it helped preserve angles of roads: “The first launch of Maps actually did not use Mercator, and streets in high latitude places like Stockholm did not meet at right angles on the map the way they do in reality.”
What projection is WGS84?
World Geodetic System
The Global Positioning System uses the World Geodetic System (WGS84) as its reference coordinate system. It’s made up of a reference ellipsoid, a standard coordinate system, altitude data, and a geoid. Similar to the North American Datum of 1983 (NAD83), it uses the Earth’s center mass as the coordinate origin.
What coordinate system does Google Maps use?
World Geodetic System WGS84 standard
The Maps JavaScript API uses the following coordinate systems: Latitude and longitude values, which reference a point on the world uniquely. (Google uses the World Geodetic System WGS84 standard.) World coordinates, which reference a point on the map uniquely.
What is the difference between Epsg 4326 and EPSG 3857?
EPSG: 4326 uses a coordinate system on the surface of a sphere or ellipsoid of reference. EPSG: 3857 uses a coordinate system PROJECTED from the surface of the sphere or ellipsoid to a flat surface. Think of it as this way: EPSG 4326 uses a coordinate system the same as a GLOBE (curved surface).
What is the difference between UTM and WGS84?
The difference is that WGS 84 is a geographic coordinate system, and UTM is a projected coordinate system. Geographic coordinate systems are based on a spheroid and utilize angular units (degrees).
How to display WGS 1984 Web Mercator ( auxiliary sphere )?
How to display WGS 1984 Web Mercator (Auxiliary Sphere) services in Google Earth? The basemap services provided by Esri (on ArcGIS Online, Data and Maps for Sever, and the Data Appliance for ArcGIS) use the WGS 1984 Web Mercator (Auxiliary Sphere) spatial reference (WKIDs 102100 or 3857).
How is the Mercator projection used in navigation?
WGS 1984 Web Mercator and WGS 1984 Web Mercator (Auxiliary Sphere) use a conformal projection that preserves direction and the shape of data but distorts distance and area. Published in 1569 by Gerardus Mercator, the Mercator projection was created for use in navigation.
How are continents shown on a WGS 1984 map?
The maps display the continents plus a 15×15 degree graticule that covers the entire surface of the earth. 1) WGS 1984: The 15×15 degree graticule cells appear as squares. The map uses a modified Plate Carree projection to display the latitude and longitude values.
Can you use WGS 84 in Google Earth?
In fact, if I display a service in Google Earth from my own ArcGIS Server instance, I can often get Google Earth to crash. Older versions of ArcGIS Online services, such as the ESRI_Imagery_World_2D service, use WGS 84 (WKID 4326) as the spatial reference, and these are projected correctly in Google Earth.