History
The Astronomical Observatory of Sofia University “St. Kliment Ohridski” signifies the resurgence of culture, science, and education in the young Bulgarian state after its liberation. At the turn of the century, it became a significant accomplishment for both the University and growing Bulgarian science.
The Observatory, photographed on 26 November 1899 by Jordan Kovachev, the first assistant in Astronomy.
At the initiative of Prof. Bachevarov, the first lecturer in Astronomy at the Higher School (as the University was originally known), construction of the Astronomical Observatory began outside the boundaries of Sofia, in proximity to the present-day “Maria Luisa” swimming pool. At that time, what is now Borisova Garden was grazing land belonging to the village of Slatina, which extended as far as Eagle Bridge. The original building and the Large dome were completed in 1897, 30 years before the foundations of the Rectorate were laid.
The Telescope of Dr. Petar Beron
The first observational instrument of the new observatory was the telescope of the renowned Bulgarian National Revival scholar Dr. Petar Beron. In 1886, his nephew Stefan Beron donated it to the Bulgarian Literary Society, which in turn presented it to the Higher School in 1892. The telescope was manufactured in Munich during the second half of the 19th century by the company “Merz” and has a magnification of approximately 500 times. It was the first observational instrument used for astronomy education. Today, the telescope, along with other astronomical instruments from the early days of the Observatory, is on permanent display at the National Polytechnic Museum in Sofia.
15 cm refractor, in operation at the Observatory since 1897
Over the course of several years, Prof. Bachevarov acquired many astronomical instruments, the most important of which is an equatorially mounted Grubb telescope with a 6-inch (15.2 cm) objective. This is the first telescope on a permanent foundation in Bulgaria. Since 1897, it has been used for astronomy education at the University and remains in operation today following its restoration in 2004.
Practical sessions at the Observatory (1921)
The Observatory in 1931
The Observatory in 1945
The University Astronomical Observatory is one of the first observatories in the Balkans. In its early years, its primary activity was educational, with scientific observations being carried out only occasionally. In 1910, Prof. Bachevarov observed Halley’s Comet, while the student A. Kunchev calculated the comet’s ephemerides. The young assistant Kiril Popoff published his observations of Halley’s Comet, made at the Observatory, in two articles in the Comptes Rendus of the French Academy of Sciences. Records have also been preserved of observations and recalculations of solar and lunar eclipse conditions made by Bachevarov, as well as occultations of stars by the Moon.
The Observatory from the air (1934)
The next director of the Astronomical Observatory and the department, Academician Nikola Bonev (from 1928 to 1965), modernised the Observatory to a European standard. The grounds were expanded, a new building with a lecture hall for classes and a terrace for astronomical observations was constructed, along with a second, smaller dome. From 1942, the Observatory was designated by law as the Time Service. It fulfilled this important role until 1986. At the dawn of the launch of the first artificial Earth satellites, the Observatory actively participated in their observation. Today, for the purposes of undergraduate and postgraduate astronomy education, the Observatory is equipped with modern instrumentation — telescopes, CCD cameras, a spectrograph, and more.
Prof. Marin Bachevarov
Prof. Marin Bachevarov (born in Gorna Oryahovitsa in 1859, graduated astronomy from the Moscow University). He began teaching the first course in astronomy in the spring of 1892, when he established the Department of Astronomy.
Acad. Kiril Popoff
From September 1904 to 1914, Acad. Kiril Popoff (1880–1966), a world-renowned mathematician and celestial mechanician from Shumen, served as assistant at the Department. His diploma was the first issued by the young Sofia University to be recognised as equivalent to French university degrees. He was the first Bulgarian doctor of astronomy (Doctor of Celestial Mechanics at the Sorbonne, 1912).
Acad. Nikola Bonev
On 1 December 1928, the Department was taken over by a former student of Academician Kiril Popoff, who later became an academician, as a regular associate professor — Nikola Bonev, born on 11 July 1898 in Stara Zagora. Acad. Bonev led Bulgarian astronomy for more than 40 years. His lectures on Spherical Astronomy were published in 1940. In addition to astronomy, he also worked in geodesy, introducing a course in geodesy in 1931 and advanced geodesy from 1940/41.