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The WGS 84 datum surface is an oblate spheroid with equatorial radius a = 6 378 137 m at the equator and flattening f = 1 ⁄ 298.257 223 563. The refined value of the WGS 84 gravitational constant (mass of Earth's atmosphere included) is GM = 3.986 004 418 × 10 14 m 3 /s 2. The angular velocity of the Earth is defined to be ω = 72.921 15 × ...
EPSG:3857 - Web Mercator projection of WGS 84, used for display by many web-based mapping tools, including Google Maps and OpenStreetMap. EPSG:9989 - International Terrestrial Reference Frame 2020 (ITRF2020) for 3D coordinates (latitude, longitude, ellipsoidal height) with subcentimeter accuracy, used for monitoring continental drift among others.
The first EGM, EGM84, was defined as a part of WGS84 along with its reference ellipsoid. WGS84 combines the old GRS 80 with the then-latest data, namely available Doppler, satellite laser ranging, and Very Long Baseline Interferometry ( VLBI ) observations, and a new least squares method called collocation. [ 3 ]
Web Mercator, Google Web Mercator, Spherical Mercator, WGS 84 Web Mercator [1] or WGS 84/Pseudo-Mercator is a variant of the Mercator map projection and is the de facto standard for Web mapping applications. It rose to prominence when Google Maps adopted it in 2005. [2]
Specifics: topography layer(s), 1px= 930m (30"arch), World (landmass only), datum WGS 84. Files: on command, 1 tiles. Files: on command, 1 tiles. — ♣ Comment(s): While ETOPO have to be the whole earth, this once can be a selected area such as Spain, and thus 'may be' more convenient for country-size project.
The National Spatial Framework for India uses Datum WGS84 with a LCC projection and is a recommended NNRMS standard. Each state has its own set of reference parameters given in the standard. [ 8 ]
On 7 January 2024 move to IGS20 happened, so WGS 84 is now aligned with ITRF2020, including PSD (post-seismic deformation), also called G2296. On the other hand GLONASS is using PZ-90.11, which is close to ITRF2008 at epoch 2011.0 and is using 2010.0 epoch (that means when you use reference transformation to PZ-90.11 you will get January 2010 ...
A geodetic datum or geodetic system (also: geodetic reference datum, geodetic reference system, or geodetic reference frame, or terrestrial reference frame) is a global datum reference or reference frame for unambiguously representing the position of locations on Earth by means of either geodetic coordinates (and related vertical coordinates) or geocentric coordinates. [1]