The Gauss–Boaga projection is a map projection used in

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

that uses a

Hayford ellipsoid The Hayford ellipsoid is a geodetic reference ellipsoid, named after the US geodesist John Fillmore Hayford (1868–1925), which was introduced in 1910. The Hayford ellipsoid was also referred to as the International ellipsoid 1924 after it had b ...

Naming and History

The projection is named after

Carl Friedrich Gauss Johann Carl Friedrich Gauss (; german: Gauß ; la, Carolus Fridericus Gauss; 30 April 177723 February 1855) was a German mathematician and physicist who made significant contributions to many fields in mathematics and science. Sometimes refe ...

and

Giovanni Boaga Giovanni Boaga (February 28, 1902 – November 17, 1961) was an Italian mathematician and geodesy professor. He was born in Trieste and died in Tripoli, Libya. His Gauss-Boaga Projection is the standard projection used in Italian topography by ...

. It was created by

in the 1940s who was at that time the head of the

Istituto Geografico Militare The ''Istituto Geografico Militare'' (IGM), or Military Geographic Institute, is an Italian public organization, dependent on the Italian Army general staff (''Stato Maggiore dell'Esercito''). It is the national mapping agency for Italy. Over ...

. The projection method is a slight variant of the Gauss–Krüger series development for the ellipsoidal

transverse Mercator projection The transverse Mercator map projection (TM, TMP) is an adaptation of the standard Mercator projection. The transverse version is widely used in national and international mapping systems around the world, including the Universal Transverse Mercat ...

. Like the closely related

UTM UTM may refer to: Computing * Unified threat management, an approach to network security * Universal Turing machine, a theoretical computer * Urchin Tracking Module, a Web analytics package that served as the base for Google Analytics * Usabil ...

, the Gauss–Boaga scales the projection down so that the central meridian has a scale factor of 0.9996 rather than 1.0.

Specifications

The grid system is based on the Roma 1940 datum, whose origin lies at

Monte Mario Monte Mario (English: Mount Mario or Mount Marius) is the hill that rises in the north-west area of Rome (Italy), on the right bank of the Tiber, crossed by the Via Trionfale. It occupies part of Balduina, of the territory of Municipio Roma I ...

near Rome. The coordinates at this point were measured 1940 as φ = 41° 55' 25".51 and λ = 12° 27' 08".40.

Subdivisions

The projection is split into a western (

EPSG EPSG Geodetic Parameter Dataset (also EPSG registry) is a public registry of geodetic datums, spatial reference systems, Earth ellipsoids, coordinate transformations and related units of measurement A unit of measurement is a definite ...

:3003) and eastern zone (EPSG:3004). The western zone is also referred to as Monte Mario / Italy zone 1 or Rome 1940 / Italy zone 1. It is used in Italy on- and-off shore west of the 12 °E longitude. The eastern zone is also referred to as Monte Mario / Italy zone 2 , Rome 1940 / Italy zone 2. It is used on- and off-shore east of the 12 °E longitude.

References

{{DEFAULTSORT:Gauss-Boaga projection Map projections Conformal projections