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first star maps was prepared by Eudoxus (408-355 B.C) who also
knew the length of the solar year almost exactly 365.25 days.
Aristoteles (384-322 B.C) formulated the argument for the sphericity
of the Earth and first hints of gravity was considered. Around the end
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of the 3 century the spherical coordinates were introduced.
Aristarchus (310-250 B.C.) attempted to determine the dimensions
and distances of the Moon and the Sun. About half a century later, the

motion of the obliquity of the Earth’s spin axis was introduced.
Eratosthenes can be called the proper founder of geodesy.
In the centuries following the fall of the Roman Empire, during
the Middle Ages, geodesy came more and more within the detrimental

embrace of theology. The major explorations got under way at the end
th
of the 15 century with Columbus (1492), Vasco da Gama (1497),
Magellan (1519). The expanding geographical knowledge prompted

the growth of a new profession: map making and cartography.
Amerigo Vespucci (1451-1512) prepared the first maps of the North
America Pacific coast and provided a name for the continent.

Mercator can be considered to be the father of modern cartography.
Indications of an impending revival of geodesy can be found in the
th
mid-15 century (Copernicus, Kepler). Galileo (1564-1642) progress
in theory Kepler(1571-1630) and the invitation of telescope. Gravity
was introduced by Stevin (1548-1620). Snell (1591-1626) carried out
the first accurate triangulation and study of refraction. Picard in 1670
made the first modern measurement of the Earth (6275 km). The

Newton’s law of the universal gavitational attraction was the most
important discovery in this era (1687).
Networks of points whose horizontal positions were determined

from the measurements of angles and occasional distances, known as
triangulation networks, was started to be used to support the mapping.
Laplace founded modern celestial mechanics, theory of tides. Gauss
th
defined the geoid, invented the least square methods. In the 19
century, most of the tools applied mathematics used in geodesy today
were invented. Euler (1707-83), Lagrange (1736-1813), Fourier(1768-
1830).
th
The beginning of the 20 century Eintein’s theory of relativity (a
further generalization of Newton’s theory of gravitation) affects the
th
thinking of physicits. The mid 20 century saw the dawing of the
technological revolution. Prompted by weapons and defence
nd
requirements during the 2 World War, the invention of a radio

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