I don´t know how many times I have gone by the Kuffner-Sternwarte in the greenbelt of Ottakring, Vienna´s 16th district, and never gone inside. This grave omission has now been remedied, thanks to the very informative (and free) history tour given by a volunteer of the Kuffner-Sternwarte Association.
When it comes to Ottakring, most of you will be familiar with the beer brewery, or at least its products. But did you know that there is actually a connection between the brewery and the star observatory? (If not, don´t feel bad, neither did I before I took this tour.)
This historic 19th century building was designed by the architect Franz v. Neumann jun. and realized by Anton Zagorsky according to Neumann’s plans. It was built for research, the second such research observatory in Vienna. (The first was the observatory of the University of Vienna, built 1874–1879.)

But where´s that beer connection, you ask? That has to do with the man it is named for.
An industrialist with a good heart
The construction of the historic observatory right across from the Ottakringer Bad (now a much frequented public pool) was funded by Moriz von Kuffner in 1884-86, who generously donated a lot of money to science and other causes.
Moriz von Kuffner was born in Ottakring in 1854. His father Ignaz, who was the mayor of Ottakring for a while, had bought a brewery in Ottakring in 1850 together with his cousin Jacob, which became very successful. Moriz von Kuffner entered the family business after completing his studies in chemistry at the Technical University. He became a wealthy business man with a knowledge of science and a heart for the poor, following in his father´s footsteps of philanthropy. (In 1878, Moriz’s father, Ignaz Kuffner, was given a nobility title, in particular because of his humanitarian merits.) Not only did Moriz von Kuffner finance the construction of the Kuffner observatory, he was also one of the founders of the meteorological station at Sonnblick, and supported other scientific endeavours.
But beyond science, this multi-talented, educated and kind man also generously funded social projects and art as well , and created a foundation for incapacitated firemen and their families. He was an honorary member of the association “Settlement”, which provided for poor children and their mothers (to which he provided the first quarter), a member of the “scientific club”, of the electrical engineering association, the ornithological association, the music friends, the industrial club and the Austrian automobile club.
A historic observatory built in “historicism” style

The architect Neumann was influenced by the University Observatory, which had been built ten years earlier. In addition to the brick construction, which was often applied to buildings in historism style, he also took over the cross-shaped floor plan, which allows a convenient combination of residential and administrative tracts with the centrally located observatory. After only two years, in the summer of 1886, the construction was completed.

At the intersection of the crossbar sits a strikingly large masonry pillar, which supports the large telescope above. All instruments rest on their own foundations, disconnected from the building, to ensure vibration-free clear images.

A separate tract to house the large heliometer was added on in 1890-91. Among other rooms this tract also contains a library, which has an unusual layout in that it surrounds the cone-shaped support pillar for the heliometer.


Famous astronomers at the Kuffner Observatory
Several notable astronomers worked at this facility. Among them Samuel Oppenheim (1857-1928), Johann Hartmann (1865-1936), Gustav Eberhard (1867-1940) (best known for his work in the field of photographic photometry.)
Karl Schwarzschild (1873-1916) is probably the most famous astronomer who worked (from 1896 to 1899) at the Kuffner Observatory. Two discoveries are closely linked to his name: The Schwarzschild exponent, which describes the blackening of photographic emulsions at long exposure times, and the Schwarzschild radius, the critical, mass-dependent radius that an object must reach in order to avoid the light being able to leave the surface due to the gravitational acceleration (i.e. the radius of Black holes!).
A terrible injustice
After all the Kuffner family had done for Vienna, when the Nazi regime came to power in 1938, Moriz von Kuffner, who was Jewish, was forced to leave with his son (his wife had died earlier that year), after the Nazis had confiscated – or acquired for a pittance under pressure – all his family´s property.
In order to be able to leave Austria for safety at all, however, a high “Reichsfluchtsteuer” (flight tax) had to be paid. Moriz von Kuffner paid a total of more than 2.5 million RM ,for himself, his granddaughter Vera and his daughter-in-law Helene, who had lost their Swiss citizenship with their marriage. What remained were the amounts on blocked accounts, which the family could not touch. On July 13, 1938, Moriz`s son Stephan took his already sick old father to Bratislava. From there they fled, probably together with the other surviving son Hans, on 7 or 8 August 1938 to Switzerland.
At the beginning of 1939, the library of Moriz and Stephan Kuffner, confiscated by the Gestapo, became a victim of the raid by the then Nazi-run Austrian National Library. Their extensive collection, which contained many thousands of volumes, was transferred to the National Library. The Nazis used the Kuffner observatory building for various purposes not related to astronomy.
Moriz von Kuffner died only a few months after the escape, on 5 March 1939 at the age of 85 in Zurich.
Many of his relatives were murdered during the Holocaust. None of Kuffner´s family ever returned to live in Austria, some of his descendants now live in the USA.
The Kuffner Observatory today
The entire complex of buildings that remain today and their old instruments have been beautifully restored and are still functional.
The meridian circle of the Kuffner Observatory was the largest of the entire Danube monarchy; today it is the largest meridian circle in Austria and one of the largest in Europe. This instrument probably contributed most to the fame of the Kuffner Observatory in the years 1887-1916.

As a non-technical person with very little knowledge about astronomy, I was mostly interested in the historic aspects, the architecture and furnishings of the observatory. Still, I could appreciate the beauty and technical intricacy, so amazing given that they were built in an age predating electricity. One of these is the impressive heliometer, an instrument originally designed for measuring the variation of the sun’s diameter at different times of year, but applied to measure the distance to stars.

Another technical masterpiece is the great refractor (or refracting telescope), through which one can still look at the stars during open days at the observatory. In its hey day, the main field of application was the measurement of fixed star parallaxes, i.e. the determination of distances of fixed stars. This impressive instrument, which stems from 1887, has been restored almost to original specifications. With a focal length of 3,5 meters and a lens diameter of 27 cm it is still an impressive instrument today. It used to be turned steadily over a course of (not quite) 24 hours by a system of pulleys powered by pendulums that had to be wound up every couple of hours. Nowadays, when it is turned for demonstration purposes, there is a motor to assist with this task, but the underlying mechanism is still the original one.


The interior design of the observatory has also been adapted to the requirements of a modern educational institution, always taking into account aspects of conservation.
The rooms contain much of the original furniture, and almost all the floors are original parquet as well. Charmingly, there are two beds that kind of resemble posh deck chairs that were used by astronomers to look through the refractor — they needed to lie down and could adjust their position by pulling on some ropes. Usually they would be lying there all day during their scientific efforts, so having a comfortable spot was quite essential! Another little detail I liked is a sort of adjustable high chair, a nifty low-tech solution to the problem of having to adjust the sitting position to different levels depending on where the telescope had to be pointed. I think some of our modern-day furniture stores may have copied this concept…
The only elements of the original setup that are no longer part of the observatory now are the previously large, north-facing park, which reached down to the Liebhartstal, and the Mirenhaus, and a small additional building for meridian measurements, which stood in the small wooded area to the left of the entrance in the garden.
Remembering a great man and his family
In 2006 the main-belt asteroid 12568 Kuffner was named in honor of Moriz von Kuffner’s sponsorship of astronomy.
On April 25, 2017, the association Steine der Erinnerung revealed a new remembrance plaque at the Kuffner Observatory in Ottakring with the support of the Kuffner-Sternwarte Association. The plaque commemorates Moriz von Kuffner and his family. A ceremony took place in the presence of the great-grandchildren of Moriz von Kuffner, as well as the descendants of Karoline Kuffner, and their families.
Leaflets with more information on Moriz von Kuffner are available at the observatory in German and English, courtesy of the Kuffner-Sternwarte association.
(My sources for all information on the history of Kuffner-Sternwarte were the tour guide, the websites of the observatory and Ottakringer Brewery, and Wikipedia)

The Kuffner-Sternwarte association has been active since 1982, originally founded to save the observatory from complete decay. After the building and instruments were restored by the City of Vienna in the 1990s, the association devised a comprehensive public outreach programme.
The Kuffner-Sternwarte is open to the public for tours and star-gazing several times a week (weather permitting) and offers other educational programmes as well.
- Open for sky observations with the Great Refractor telescope from 1887 every Sunday and Monday from 9 pm in any weather (except you won´t see much if it is cloudy), and Wednesday and Thursday from 9 pm only in precipitation-free weather
- Historic observatory (building) tours take place every Sunday at 8 pm
- Sun observation every third Sunday of the month at 4 pm
All types of tours, courses and events can be found on the observatory´s website under events (Veranstaltungen).
Other opportunities to watch and learn about the stars in Vienna: