The first 100 years

Observatory at Popov Tower – a century in the service of astronomy

Tatjana, Kren, prof

At the turn of the 19th and the 20th centuries, when the Observatory of Croatian Natural History Society on Popov Tower was founded, Zagreb became a modern political, cultural and economic center of Croatia, especially its north-western parts, which was increasingly linked to European flows. Together with the development of industrialization, Zagreb achieved a significant rise in the process of creating a modern civil society. It was the headquarters of the main political parties, most famous political figures, writers, artists, scientists, journalists. Newspapers and other mass media and scientific literature, influenced the formation of public opinion. Every seventh resident of Zagreb was a student of an elementary or secondary school, or a student at the University.


The establishment of the Observatory and the first decade of activity


Until the 19th century and the development of modern astronomy, Croatians had in their history a large number of well-known scientists and philosophers who have studied astronomy and achieved valuable results, from Hermann the Dalmatian from the 12th century, through Ivana Vitez of Sredna (15th century.) , Franjo Petris (16th c.) and Ruder Boskovic (18th c.).
In 1885, a university professor Spiridion Brusina, together with his colleague and friend Djuro Pilar and several other colleagues, founded in Zagreb The Croatian science  society, the first society of natural science in Croatia and generally in the Slavic south. It was founded on the Assembly which was held on December 27th 1885 at the National Museum in Demetrova street number 1 in Zagreb’s Upper Town, where Brusina was elected as the first president. The society has brought together scientists, but also lay people of different occupations who were interested in science. Regular members were from different Croatian cities, but among them were also members outside Croatia: Vienna, Arad, Budapest, Sarajevo, Prague, Milanovac and Belgrade.
The first years of the Croatian science society had two sections: a geographical and a ornithology section, and astronomy was present in the actions of individual members of society. Society member Dr. Oton Kucera, was a writer of very popular astronomical books – Our sky. Oton Kucera was the initiator of the founding of The Observatory and its first governor until 1913.
In 1902 he established a private astronomical section, with a goal to establish The Observatory for scientific and professional work and popularization of astronomy. The Society has established a Committee of the Croatian Natural Society for organizing The Natural science astronomical Observatory in Zagreb and addressed the people, the city and the government, seeking financial support for the purchase of the main telescope and the renovation of the Observatory. The chairman was the president of the Society, dr. Dragutin Gorjanović and members were: Dr. Oton Kucera, dr. Francis Spevec, famous Croatian author Ljubo Babic – Ksaver Sandor Gjalski, dr. Antun Heinz and Francis Sandor. The committee fairly quickly managed to fully realize almost all the tasks: to find funds for the first investment donation from the City Council and contributions from citizens, get a better main binocular (Reinfeld and Hertel company from Munich, made in 1901, with aperture of 6.4 inches or 162.6 mm), find a suitable place to accommodate The Observatory (old city defense tower from the 13th century Popov Tower (Priest’s or Bishop’s tower)) and from the city officials to obtain a place (on February 2, 1903, the city Assembly adopted a decision for Popov Tower to be assigned to the Society, for the purposes of the observatory), make a movable dome for binoculars and it was taken into account that the construction of the observatory must be carried out according to strict scientific requirements.
In the early 1905, the Observatory has received a photographic camera, the astronomical clock and micrometer, and collaborated with several European observatories. Two observatories in Germany offered their scientific cooperation. During those years some observations were carried out in The Observatory, the staff observed the sunspots and the solar eclipse, but the scientific results were very limited, and it was the same in following years, although the Observatory had more instruments. The negative contributing factor was also the failed attempt to establish The Department of Astronomy at the University of Zagreb in 1906. In 1909. there was an another attempt to build a new observatory, exclusively for scientific research, in Prozorje near Dugo Selo, which failed. Contrary to the insufficient scientific work, activities for promoting  astronomy were very successful. The Observatory was visited by numerous citizens and school groups from Zagreb and other parts of the Croatia. Max Wolf, the director of the Heidelberg Observatory, in agreement with the discoverer of the planeteoid 589, Augustus Kopf, discovered in 1906, the name Croatia, in honor of the opening of The Croatian Observatory in Zagreb.

The First World War and the Postwar Years


Portrait of Otona Kučere made in the memory of the 50th anniversary of his public and educational work and the 70 anniversary of his life (Lucija Kučera-Buhmeister, oil on canvas)

Following Kučera’s departure from the director’s post  in 1913, the Society decided to organize the Observatory mainly for the purposes of the popularization of astronomy and suspended all expansions planned  for the Observatory. There were only two staff members at that time on the Observatory, the director Dr. Vlado Drapczynski and Miro Mance. The observations of the planets continued, as well as the assessment of time and the reception of visitors.
At the beginning of the First World War in 1914, the work of all societies was suspended and the Observatory was also closed. The Society entrusted the care of the inventory of the Observatory to prof. Adam pl. Kugler, and from 1915 he was also the head of the Astronomical Section. He edited the Meridian Circle and regularly determined the exact time, and despite the war, in 1918 he printed a circular star chart in the edition of the Observatory, the first of its kind in Croatia and the Slavic South. In the spring of 1917 the Observatory was opened for several months, and Kugler managed to print the astronomical calendar Bošković for the 1918, the first of its kind in the Slavic south.
After the death of Professor Kugler in 1918, the position of the director of Observatory was taken over by prof. M. Hubej, but he soon died, and in 1920 the Society again invited dr. Kučera to accept the office of the Observatory. Kučera was initially assisted by students Franjo Bošnjaković and his son Vlaho Kučera, and also Dr. Vladoje Drapczynski who returned later. Instrumental repairs were carried out with the government support and with voluntary works. The Observatory was the most successful in promoting astronomy among Croatian people.
The Bošković calendar came out regularly until 1926, when it stopped coming out because of financial difficulties. After A. Kugler it was edited by Željko Marković, and by Kučera for the years 1924, 1925 and 1926.The extent of work on the Observatory was almost exclusively in receiving visitors, holding lectures and displaying celestial objects. In 1923, in the twentieth anniversary of the Observatory and the second mandate of Kučera management, it was noted that the Observatory was visited by 2100 people, and also by students who were received in groups. It was open three times a week, and on Sunday there were regular observations of the Sun, which validates the great activity of the Observatory, but this activity lasted only while the Observatory was managed by Kučera.