Astronomy in the divided City of Berlin
Astronomy at the Universities of West-Berlin
Dr. Jens-Peter Kaufmann
This article is part of a volume published in 1998 by the Berlin Observatories to commemorate the 100th anniversary of the Archenhold-Sternwarte and the 50th anniversary of the Wilhelm-Foerster-Sternwarte in 1997. (It is a fitting coincidence, that the Institut also celebrated an anniversary in 1997: its 25th)
After World War II, due to the new boundaries drawn in 1945, there were neither an astronomical observatory nor other places for astronomical research in West-Berlin. At that time this was not felt as a loss, as observing astronomy is rather senseless in a big city with its air- and light- pollution. After the first years of reconstruction, however, when the division of Germany and Berlin appeared to be permanent, the need for astronomy as a subject of research and education became apparent. Therefore a chair for astronomy was established in 1954 at the 1. Mathematical Institute of the Free University (FU), following the historical development of classical astronomy (until 1850) as mainly mathematically defined celestial mechanics. The professor of the chair, Fritz Hinderer, mainly did research on variable stars, using his comprehensive observations collected at the Observatory of Babelsberg. Students belonging to the faculty of Mathematics and Natural Sciences were given the option to choose Astronomy as a minor subject. They received their observational training at the Wilhelm-Foerster-Sternwarte, West Berlin"s public observatory.
At the Technical University (TU) the call for an astronomy department came from among the physicists. Hermann Slevogt of the Optical Institute can be credited a major role in establishing the Chair for Astrophysics (1968) at the university. The word astrophysics was intentionally chosen to define astronomy as a subject of the faculty of physics, expressing the fact that since 1850 astronomy has been considered a branch of physics. Coming from the Kiel school of Professor Unsöld, Kurt Hunger was appointed first professor of the chair. Accordingly the physics of stellar atmospheres became the main subject of his scientific work. In addition to this, Jürgen Rahe committed himself to the study of comets. Stellar spectra, the observational material for the analysis of stars with abnormal high helium abundances, were obtained at external observatories, mainly at the European Southern Observatory (ESO) on la Silla mountain in Chile. For the training of the students in Berlin, a 40 cm reflecting telescope was purchased in 1973 and placed on TU-grounds in Berlin Dahlem (Hellriegelstraße).
In 1972 the Chair (Lehrstuhl) for Astrophysics was transformed into an Institute to secure more permanence for this Institut für Astrophysik at the TU. In the following years the physics of stellar atmospheres was extended to calculations of atmospheres not in thermodynamical equilibrium. During seven years very productive work was performed in investigating the He-rich stars.
The year 1978 brought a change in many respects. After Kurt Hunger had become the successor of Albrecht Unsöld in Kiel (1976), Roland Wielen of the Astronomisches Recheninstitut in Heidelberg took on the leadership of the TU-Institute in 1978. In 1979 he succeeded in combining the two astronomy groups at FU and TU to one institute at the TU, named "Institut für Astronomy und Astrophysik", which coordinated astronomical teaching at both TU and FU.
The institute"s new name was chosen to express the fact that modern astronomy is primarily astrophysics, but the name also reflects the long history of astronomy and the natural sciences and their heritage. In 1980 the institute had a faculty staff of 3 professors, 1 university councilor, 5 scientific coworkers, 5 tutors, 1 programmer, 1 technical assistent, a full-time secretary, a half-time secretary and about 15 students aspiring after a diploma or doctor"s degree. At both universities physicists, geophysicists, mathematicians, meteorologists and others were given the choice to select Astronomy and Astrophysics as a compulsory subject during the advanced studies period. At the TU, due to the strong interest of the students, the subject was introduced (1984) also as a compulsory subject during the four semesters of the basic studies period.
Klaus Beuermann joined the institute in 1980, when the pedagogic colleges were integrated into the universities. Then Erwin Sedlmayr from the Institute for Theoretical Astrophysics in Heidelberg filled the position of Professor Fritz Hinderer, who had retired in 1978. For a couple of years the combined institute"s spectrum of research topics broadened quite a bit.
Jens-P. Kaufmann continued pursuing research of He-rich stars in the section stellar astrophysics. Klaus Beuermann mostly worked on "X-ray binary stars. Erwin Sedlmayr pursued the subject of dust formation and growth" in shells of red giant stars. Roland Wielen introduced the "dynamics of stellar systems" into Berlin"s astrophysical research. He also played a vital role in the planning of the astrometric satellite HIPPARCOS. During his seven years in Berlin the institute"s library was expanded and was made a special section (Sonderstandort) of the university library.
In 1985 the institute was able to leave the former AEG-Telefunken building at Ernst-Reuter-Platz, and move into more appropriate rooms in the new physics building in Hardenbergstrasse. An additional telescope, a 20 cm refractor, was installed in a dome on the roof of the new building. That year Roland Wielen was appointed director of the Astronomisches Recheninstitut in Heidelberg. This caused a shift in the main scientific research activities. While the undertakings concerning the dynamics of stellar systems were abolished after a few years, activities in the remaining fields were increased. E. Sedlmayr created special groups which engaged in hydrodynamics, radiation transport, formation of molecules, and interstellar dust. K. Beuermann worked mainly on optical and x-ray observations of cataclysmic variables and x-ray binaries as well as their accretional discs, but also of active galaxies. Both topics of research were the main topics of the spring symposium held by the Astronomische Gesellschaft in Berlin in 1990 entitled "accretion and winds" (Akkretion und Winde). This event was the first one since 1945 that allowed astronomers from East- and West-Germany to come together without any restrictions.
After K.Beuermann had followed a call to Göttingen in 1991 and E. Sedlmayr had been appointed C4-Professor of the institute in 1995, the field of research at the institute became still more homogeneous. Today it generally spans the formation of molecules and dust i.e. the origin of the first solid in the universe, touching areas such as astrochemistry, biomolecules, and life in the universe.
The gradual development of astronomy in West Berlin shows some typical hallmarks of modern astronomy at a university. Research and education are more integrated now in the overall concept of the faculty of physics. The astrophysical research of the cosmic circle of matter is one of its main subjects of research (Forschungsschwerpunkt). These subjects are in many respects closely connected and organically interrelated. During more than 25 years of teaching astronomy, we noticed a growing interest in the subject by students of different faculties: physics, geophysics, mathematics, chemistry, space technology, but also philosophy and history of science. Astronomy with its long history and its specific way of asking questions to nature is obviously still very attractive to young inquisitive people.
It is a challenge and task for the future, to increase awareness of the important interdisciplinary role and integrating function of astronomy at a university and to strengthen it by adapting the direction of research, lectures and exercises to more general questions of scientific interest.