- •Introduction
- •Chapter 1 History of Geodesy
- •Chapter II Figure of the Earth Part 1
- •Figure of the Earth Part 2
- •Ellipsoid of Revolution
- •Chapter III Geodetic Surveying Techniques
- •Horizontal Positioning
- •Triangulation
- •Text 10
- •Orders of Triangulation
- •Text 11
- •Trilateration
- •Text 12
- •Traverse
- •Text 13
- •Celestial Techniques
- •Text 14
- •Vertical Positioning
- •Text 15
- •Chapter IV Geodetic Systems
- •Text 16
- •Orientation of Ellipsoid to Geoid
- •Text 17
- •Text 18
- •Text 19
- •Text 20
- •Text 21
- •Text 22
- •Text 23
- •Text 24
- •Text 25
- •Text 26
- •Chapter V Physical Geodesy
- •Text 27
- •Text 28
- •Text 29
- •Text 30
- •Text 31
- •Text 32
- •Text 33
- •Text 34
- •Text 35
- •Text 36
- •Chapter VI Satellite Geodesy
- •Text 37
- •Text 38
- •Text 39
- •Text 40
- •Text 41
- •Text 42
- •Chapter VII Other Developments in Geodesy
- •Text 43
- •Text 44
- •Text 45
- •Text 46
- •Text 47
- •Text 48
- •Text 49
- •Chapter VIII The World Geodetic System
- •Text 50
- •Text 51
- •Text 52
Text 52
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A New World Geodetic System
The need for a new world geodetic system is generally recognized by the geodetic community within and without the Department of Defense. WGS 72 no longer provides sufficient data, information, geographic coverage, or product accuracy for all present and anticipated applications. The means for producing a new WGS are available in the form of improved data, increased data coverage, new data types and improved techniques. GRS 80 parameters (Chapter II) and presently available Doppler, laser and VLBI observations constitute significant new information, which are being utilized. There are now over 1000 Doppler determined station positions available as compared to the near 100 station values used in WGS 72. Also, an outstanding new source of data is now being made available from satellite radar altimetry (Chapter VII). Among the improved techniques now employed is an advanced least squares method called collocation which provides for a consistent solution from different types of measurements all relative to the earth's gravity field, i.e geoid, gravity anomalies, deflections, dynamic Doppler, etc.
WGS (initially WGS 72) is the reference system being used by the Global Positioning System.