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information geodesy can supply. The collaboration between
geophysicists and geodesists is quite wide and covers many facets of
both sciences. As a result, the boundary between the two sciences
became quite blurred even in the minds of many geo-scientists. For

example, to some, the study of global gravity ___ fits better under
geophysics rather than geodesy, while the study of local gravity field,
may belong to the branch of geophysics, known as exploration

geophysics.
Other sciences have similar, but somewhat weaker relations with
geodesy: space science, astronomy (historical ties), oceanography,
atmospheric sciences and geology. As all exact sciences, geodesy

makes a heavy use of mathematics, physics, and of late, computer
___. These form the theoretical foundations of geodetic science.
Space science needs the knowledge of the geometry of the Earth’s

external gravity field for predicting the orbits of the space vehicles.
Space science has developed some very powerful positioning systems
that use the Earth’s artificial ___, and those are being used in geodesy.

Of common interest is the monitoring of the Earth rotation.
Another part of astronomy, celestial mechanics is also needed in
geodesy to study the satellite ___.

Geodesy provides relative heights of the on-shore water level
measuring devices and their relative vertical movement.
Oceanography provides the deviations of the mean sea ___ from an
equipotential surface of the Earth’s gravity field. This information is

needed for the establishment of a ___ for heights.
Atmospheric science looks the effect of the distribution of air
density. Geodesy needs realistic models for atmospheric refraction

which represents one of the most troublesome problems in many
geodetic measurements.
Geology requires both horizontal and vertical positions for its
maps. It provides geodesists with a knowledge of ___ and local

stability of different geological formations.

Task 2. Put up 5 general and 5 special questions to the text.

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