The increasing size of Berlin made observations at the Berlin Observatory in Kreuzberg more difficult and Foerster attempted to persuade the government to finance a new building. However he retired in 1903 and the observatory actually moved to Babelsberg during the directorship of Struve.
Hermann Struve was a third-generation member of the famous family which had effectively controlled Pulkovo Observatory, near St. Petersburg, since its inception. Hermann had become director of Pulkovo, but moved to Germany, going first to Königsberg, and then Berlin. He was an expert on Saturn .and its ring system (contributing greatly to the modern theory of the movement of the satellites of Saturn), and studied other solar-system objects, as well.
The land for the new observatory was situated at the eastern end of Babelsberg Park and was provided free, the sale of the old observatory providing the money for construction and instrumentation. This old observatory was demolished.
The new observatory came into service in 1913. The central dome was occupied by a new 65 cm. refractor, delivered in 1914, the first big astronomical instrument manufactured by Carl Zeiss Jena. When a 120 cm. reflecting telescope was installed in 1924 (being delayed because of the war), Berlin could claim to be the best-equipped observatory in Europe.
His brother was also a professor of astronomy and director of Charkow observatory.