The measurement is accomplished with the use of GPS, as geodesists are able to monitor the movement of a site 24 hours a day, seven days a week.
NOAA highlights that geodesists should accurately define the coordinates of points on the surface of the Earth in a consistent manner. A set of accurately measured points is the basis for the National Spatial Reference System, which allows different kinds of maps to be consistent with one another.
Also, many are the organisations using geodesy to map the US shoreline, determine land boundaries, and improve transportation and navigation safety. To measure points on the Earth’s surface, geodesists assign coordinates to points all over the Earth.
In the past, prior to the technological development, geodesists stated the coordinates of points by using Earth-based surveying tools measuring the distances between points.
Today, geodesists have adopted the ellipsoid as the most basic model of the Earth, the most simple mathematical model, which excludes mountains or valleys.
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