Page 206 - 4670

datums, and − connection of national datums with a global geodetic
datum.
It is also used for geodetic control, namely for:
− establishment of geodetic control for national networks, −

installation of three-dimensional homogeneous networks, − analysis
and improvement of existing terrestrial networks, − establishment of
geodetic connections between islands or with the mainland, −

densification of existing networks up to short interstation distances.
In geodynamics satellite geodesy is used to show:
− control points for crustal motion, − permanent arrays for 3D-
control in active areas, − polar motion, Earth rotation, and − solid

Earth tides.
In applied and plane geodesy it gives:
− detailed plane surveying (land register, urban and rural

surveying, geographic information systems (GIS), town planning,
boundary demarcation etc.), − installation of special networks and
control for engineering tasks, − terrestrial control points in

photogrammetry and remote sensing, − position and orientation of
airborne sensors like photogrammetric cameras, − control and position
information at different accuracy levels in forestry, agriculture,

archaeology, expedition cartography etc.
In navigation and marine geodesy satellite geodetic technologies
are used to give:
− precise navigation of land-, sea-, and air-vehicles, − precise

positioning for marine mapping, exploration, hydrography,
oceanography, marine geology, and geophysics, − connection and
control of tide gauges (unification of height systems).

With more satellite systems becoming operational, there is almost
no limit to the possible applications. Satellite geodesy also made a
substantial contribution to the deepening perspective in which men
could view their own planet. But the new perspective differed in an

interesting way from that provided in magnetospheric physics. For the
latter, rockets and satellites revealed a wide range of hitherto unknown
phenomena. In contrast the subject matter and problems of geodesy

were well known; it was increased precision, the ability to measure
higher order effects, and the means for constructing a single global
reference system that space methods helped to provide.

206