Gensio Hugo de Souza) Aiming at to uniformizar information, I understand that it is interesting to divulge for the biggest possible number of people, a little on the changes that are occurring throughout the last decades, in the area of the cartography in what it says respect to the system of geographic coordinates and its standardization. The cartographic base with DATUM SAD69 (South American Datum 1969) is with the counted days and agrees that all know. In its place the SIRGAS appeared, but unhappyly still little it is divulged. ‘ ‘ The System of Geocentric Reference for Americas (SIRGAS) has as objective to make compatible the geodesic systems of the South-american countries, being promoted the definition and the establishment of an only referencial, with compatible precision with the current technology of posicionamento’ ‘ (IBGE), geographic, with aid of satellites and the cartographic methodology on the basis of Geodesy. ‘ ‘
The adoption of the Sirgas was recommended in 7 Cartographic Conference Regional of United Nations for Americas, carried through in New Iorque in 2001. The majority of the South-american countries introduced the Sirgas as reference system nacional.’ ‘ (IBGE) Soon historical on the migration of the classic systems of reference, for the system Sirgas 2000 For users of geographic information that still have doubts on which the correct geodesic referencial to be used in such a way in the Brazilian territory as in the remain of Latin America and for professionals who desire to more than understand the subject that is world-wide trend and that it is revolutionizing in such a way the cartography as engineering. Different systems of reference for the South American countries were adopted, as PSAD56, SAD69 (South American Datum 1969), Bogota, Yacar, Field Inchauspe, etc. In 1993, were defined that all the countries of the American continent would have to use the System of Geocentric Reference for Americas (SIRGAS)…