Historical illustration of the spectrograph of the Astrophysical Observatory in Potsdam, 1870s. This observatory is now the Leibniz Institute for Astrophysics Potsdam (AIP). It is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory Potsdam (AOP) founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics.