Großenhainer baseline
Map with all coordinates: 
The Großenhainer baseline was the baseline for the Royal Saxon Triangulation and at the same time the Saxon contribution to the Central European degree measurement . It consists of three geodetic control points :
- Eastern base end Quersa (station 32 in the Royal Saxon triangle network) - Coordinates: 51 ° 18 ′ 45.1 ″ N , 13 ° 37 ′ 14.8 ″ E
- Grossenhain base center (station 33) - Coordinates: 51 ° 18 ′ 17.8 ″ N , 13 ° 33 ′ 15.2 ″ E
- western base end of Raschütz (station 34) - coordinates: 51 ° 17 ′ 53.4 ″ N , 13 ° 29 ′ 42.3 ″ E
The points were created in the years 1869 to 1872. A base house rises above a base pillar set in the ground, on which another pillar is located exactly vertically above the base pillar. Only the Quersa point still exists in this form.
restoration
From 2005 the baseline was restored.
- The Quersa point , where the base house was still there, has been faithfully restored. On the balustrade is the inscription “Basisendpunkt QUERSA d. Royal Saxon. Triangulation 1870 ", in the original it should have been called" Triangulation ".
- From the Raschütz point , the foundation pillars and remains of the foundations of the house were still there, in 2005 an apparently new granite head was placed on the pillar and the outlines of the house on the ground and upwards were reproduced by a frame made of wooden beams.
- The point at the base center of Großenhain was for many years on the site of a military airfield that is used privately today. In its place is a copy of the original base pillar at ground level.
An information board was placed at each of the points.
After the restoration, the Großenhainer baseline was inaugurated on March 17th, 2006.
use
The actual basis is formed by the two end points; the center point was used for simplification so that the individual distances could be determined separately for subsequent measurements. The base was determined by measuring the length with the Bessel measuring apparatus at 8908.648 m. Starting from the base, the length was transferred to the Collm - Keulenberg triangle side by means of triangulation, thus determining the scale of the entire triangular network.
Expansion to Upper Austria and the Adriatic
In the late 19th century, the Saxon meridional arc was also integrated into a major Austro-Hungarian project for Central European earth measurements in order to determine the exact shape of the geoid in a north-south profile.
The central part of this over 600 km long triangulation chain - the Grossenhain-Kremsmünster-Pola meridian arc - was the Upper Austrian Kremsmünster meridian arc . In the north, the Großenhainer Bogen and an intermediate chain from older measurements connected, in the south a separate first-order network through the south of Austria to the Adriatic Sea near the marine port of Pola (today Croatia). The Gusterberg not far from the Benedictine Abbey of Kremsmünster served as a fundamental point .
See also
literature
- Richard Schumann , Friedrich Hopfner : The meridian arc Grossenhain-Kremsmünster-Pola . Astronomical work of the Austrian Graduation Office, New Series Volume I, pp. 4ff and 105ff, Federal Surveying Office, Vienna 1922
Individual evidence
- ^ A b C. Bruhns , A. Nagel : Astronomical-geodetic work for the European degree measurement in the Kingdom of Saxony. (PDF) Division I. The Grossenhainer baseline. Retrieved on March 20, 2014 : " Image quote "
