Einstein Tower

Begun in 1919, work on the Einstein Tower on Potsdam’s Telegrafenberg hill was completed in 1922. The structure is an icon of the new spirit in architecture as well as the working housing for the meticulous requirements of an astronomical observatory. The tower was built collaboratively by the architect Erich Mendelsohn, the astrophysicist Erwin Finlay Freundlich, and Albert Einstein, after whom it was named. The observatory is a now part of the Leibniz Institute for Astrophysics.

Freundlich, an employee at the Babelsberg Observatory near Potsdam, sought a practical means to validate Einstein’s work on the theory of relativity through observations. He initiated a fund-raising drive and convinced his friend Mendelsohn to plan a suitable structure for the observatory. In 1919, all German newspapers featured an appeal on behalf of the “Albert Einstein Donation Fund.” This publicity ensured the funding, to which the Prussian State and German industry contributed.

The Einstein Tower project represented Mendelsohn’s professional breakthrough, bringing him international recognition. While the scientific requirements of the observatory required a separate foundation for the telescope, the architect had a free hand in designing the architectural shell. He gave the outer façade an organic form with the curves of Expressionism and Art Nouveau. Mendelsohn planned the tower as a pure reinforced, cast-in-place concrete construction. However, because the technique and the materials were not yet advanced enough, a mixed building technology of concrete and plastered brick masonry had to be used. The effect of a homogeneous concrete structure was achieved with the aid of a fine-grained, ochre-colored plaster finish.

Construction was completed in 1922, and the technical instruments were installed by 1924. While the verification of the shift of spectral lines in the sun’s gravitation field was not possible, findings in the field of solar research have been achieved at the Einstein Tower, where Potsdam’s astronomers now measure the sun’s magnetic fields. The tower underwent an elaborate renovation in 1997–99. Due to the active research being carried out in the Einstein Tower, the interior can only be visited in conjunction with a guided tour. The exterior can be viewed at any time. [KL/HY]