Federal Agency for Cartography and Geodesy


Geodesy is the science of measuring the earth. Uniform reference systems constitute the basis for surveying and navigation, as well as monitoring and exploration of global changes.

Earth is a dynamic system in constant movement and subject to continuous change. Continental drift, sea level changes, and the planet's speed of rotation is not constant. Water flows downwards with gravity, which then changes the topography and the location of water bodies. Because of this, we need fixed reference systems so that we are able to measure and evaluate these changes.

BKG's specialist department of geodesy supplies, maintains, and updates these reference systems.

BKG also takes measurements in addition to those supplied by international partners. For example, the Geodetic Observatory Wettzell, located in the Bavarian Forest, uses satellite navigation systems (such as GPS and Galileo), as well as laser ranging to the moon and other satellites, and radio-telescopic measurements to far-off radio source stars (quasars).

In cooperation with a consortium of international partners, BKG determines, on the basis of these data and many other data sources, the different coordinate, height, and gravity reference systems in order to:

  • Calculate the movements of the earth and satellites in space, as well as high-precision coordinates on the earth's surface
  • Determine precise uniform height data, such as dike heights in the context of flood prevention

These reference systems are critical in order to understand how various types of spatial data are related to each other. Precise positioning and coordinate reference systems are essential factors in the success of business, science, and administration. Vehicle data navigation systems, and even landing robots on Mars, can only be possible with accurate navigation and measurement.