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Task 2. Read and translate the following text
Text 1 Defining the position on the Earth surface ant its
depiction.
Every place has a "global address" that tells exactly where in the
world it’s located, just as your home has a street address. There are
two numbers in a global address – a number for latitude and one for
longitude. If you know these numbers and how to use them, you can
find any place in the world and give its absolute location. Location
can describe how one place relates to another. Absolute and relative
location are two ways of describing the positions and distribution of
people and places on the Earth’s surface. Absolute location is nothing
more than a simple dot, often identified as a grid coordinate on the
surface of the earth. Latitude and longitude can be used to pinpoint a
location. Relative location is the relationship of a place to other
places.
The main coordinate systems are:
a. plane rectangular (grid);
b. spherical;
c. ellipsoidal (geodetic);
d. geoidal (astronomical), which are distinguished according to
whether the plane, the sphere, the ellipsoid or the geoid is used as the
surfaces of reference. The ellipsoidal co-ordinates are also termed
geodetic, while the geoidal coordinates are the astronomical ones.
According to this interpretation, the term ‘geographical coordinates’ is
a general term which includes the ellipsoidal and geoidal types of
coordinates.
Different kind of coordinates can help to position objects in a
two- or three-dimensional space.
Spatial coordinates (also known as global coordinates) are used
to locate objects either on the Earth’s surface in a 3D space, or on the
Earth’s reference surface (ellipsoid or sphere) in a 2D space. Specific
examples are the geographic coordinates in a 2D or 3D space and the
geocentric coordinates, also known as 3D Cartesian coordinates.
Planar coordinates on the other hand help to locate objects on
the flat surface of the map in a 2D space. Examples are the 2D
Cartesian coordinates and the 2D polar coordinates.
The surface of the Earth is depicted by maps, plans and profiles.
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