Schott glass-ceramic for the "Earth's tachometer"

It is installed in an underground laboratory at the Wettzell fundamental research station in the Bavarian Forest, an observatory belonging to the German Federal Cartography and Geodetics Bureau of Frankfurt. The task of the installation is to precisely document the earth's rotation - and in particular any variations in it. This will provide scientists with important information complementing astronomical measurements and enabling them to evaluate satellite-supported navigation systems such as the "Global Positioning System" (GPS).