Peter Kroll, Bernd Müller, Eberhard Splittgerber and colleagues are astronomers, programmers and engineers who carry on the legacy of their founder Cuno Hoffmeister (1892-1968) in the sliver-grey, entirely in aluminium covered building of the Sonneberg observatory.

Hoffmeister induced the construction of the observatory on the 638 meter high hill Erbisbühl and established the world leading institute in the astronomic special field of variable stars from 1925 till the end of the 1960s.

He started the long-term project „Sonneberg Sky Monitoring“. He discovered 10.000 of the „Variables“, about a forth of all known stars: keeping with the slogan „At the end of the day, not the richness of means but the animating spirit is crucial for the success“ hasn’t lost its validity and is traded from alliance out of necessity to alliance out of necessity. After the German reunification, the observatory with its seven astrodomes and a 360 degree field of view teeters at the brink of collapse.

Through the sky photographs gained in more than 80 years (the oldest photographic plates are from 1925) the observatory Sonneberg emerged with approx. 275 000 images to the second largest archive in the world.

4 pi Systeme rescued the observatory and the enthusiastic experts founded out of necessity and opportunity a concept of software developments in the astonomic field and the construction of specialist telescopes, driven by the vision to establish a small operating organism that can maintain itself as enterprise but also offer development potential for the science.

The observatory Sonneberg is only a few kilometres from the former German-German border on a hill. It was visible from the Bavarian town Coburg during GDR times.