Physicists in the Tartu Observatory in 1952–1975

In 1946 the Tartu Observatory was subordinated to the Academy of Sciences. After its reconstruction in 1952 there was more working space, in addition to astronomers, to a part of theoreticians in physics who remained in the observatory until 1975 when the main building of the Institute of Physics was opened in Riga Street.

In 1953, on the initiative of Rector Feodor Klement (1903–1973), in the left wing of Struve’s house the luminescence laboratory or later titled the sector of ionic crystals physics started functioning. In 1966 it moved over to Riga Street when the laboratory of growing crystals was completed. On the upper floor of Struve’s house some researchers of the sector of theoretical physics started working, later the whole sector occupied the floor. On the ground floor, until 1975 the accounting office of the physics sectors worked and there were also some flats. In the former shed for coaches there was a workshop and later book-keepers worked there.

During the observatory period the Institute of Physics and Astronomy became the centre of Estonian physics. The founders of fundamental research in theoretical physics were Aksel Kipper, Harald Keres (theory of relativity) and Harry Õiglane (physics of elementary particles). The experimental physics began to develop quickly when the laboratory of luminescence was established (from 1954 the managing head of the laboratory was Tšeslav Luštšik). The broad solid physics front developed also involving theoretical studies. Rector Klement invited Karl Rebane (1955) to develop the solid physics theory in Tartu. Rebane had finished his post-graduate studies in Leningrad. Together with Nikolai Kristoffel they began to form a group of solid physics theoreticians.

The physics theoretician Nikolai Kristoffel at his desk in the Tartu Observatory

In the years of the observatory there are two important discoveries. In 1966 Elmar Vesman wrote a paper which marks the theoretical discovery of the μ-molecular ion (ddu)+ resonance mechanism (the paper was published in 1967, the discovery was registered in 1988). In 1968 Vladimir Hižnjakov, Karl Rebane and Peter Saari discovered the phenomenon of photo luminescence (the discovery was registered in 1981).

In Tartu several Soviet Union physics conferences were held. In 1970 the group of solid physics researchers organized the international physics seminar, the first in Estonia, “Physics of Impurity Centers in Crystals” in Tallinn and was a co-organizer of the 11th European Molecular Spectroscopy Congress in 1973.

The luminescence laboratory in Struve´s house was visited by E. and M. Grillot from Sorbonne University (TÜR. 72-1115: 10)