Instruments and Observatories belonging to the Institute

Austria is a member of the European Southern Observatory (ESO) and the European Space Agency (ESA). Our institute is involved in the use and further development of these most powerful Earth-based observatories and space telescopes. In addition, we also operate our own modern and historical observing facilities.

Leopold Figl Observatory

The observatory consists of two buildings. The main building houses the 1.5m reflector telescope. Astronomers can make use of working and sleeping rooms on two floors. The high-vacuum chamber used to aluminise mirrors, as well as a workshop, are located on the building’s ground floor. The second building contains a 0.6m reflector telescope, which was designed and built at the Viennese University Observatory. Further information can be found at:

The 0.8m "vlt" (vienna little telescope)

On December 10th, 2002, the „vienna little telescope” (vlt) - an 80cm (f/8.3) Cassegrain telescope -  was assembled in the Observatory’s northern dome. Design and controls were provided by the company Astro Optik, while the mechanical components were produced by Astro Technik (both German). The reflector optics were manufactured by LOMO in Russia. The vlt is equipped with a CCD photometer and is used for both research and teaching.

A 4096 x 4096 pixel CCD camera produced by the company Finger Lake Instruments has been in successful use with the vlt since September of 2017. A detailed report of the renovation of the vlt’s instrumentation can be found here.

The 1m Telescope on Hvar (Austro-Croatian Telescope)

The ACT is located on the Croatian island of Hvar on the grounds of the Hvar Observatory, near Napoleon Fortress at 238 metres above sea level. Further information can be found at:


Uni - BRITE stands for University of Vienna BRIght Target Explorer, a research satellite in cube format with an edge length of 20cm each. It is the first astronomical research satellite with this miniaturisation. From its polar orbit, it measures the extremely small variations in the luminosity of stars with high precision. This data provides valuable insights into their internal structure, their state of development and, through a comparison with our sun, also conclusions about the past and future of our central star.

The first thoughts about an Austrian nanosatellite were made in September 2004. UniBRITE was launched from India on 25 February 2013 with a PSLV-C20 rocket and, for cost reasons, with a number of other small satellites as "passengers" to a large satellite. However, its completion had been delayed by more than three years and with it the launch of UniBRITE.

This satellite of the University of Vienna is an important contribution to one of the three research topics of the Institute of Astronomy, namely "Stars and Planets".

The 27-inch Grubb Refractor

The Institute for Astronomy’s 27-inch refractor was built in Dublin by Grubb and is located in the large dome (14 meters in diameter) in the middle of the observatory. At the time of its completion, it was the largest refracting telescope in the world. At 10.5 meters long, its total weight is 13.5 tons (including the pedestal). The moving parts themselves weigh 5.5 tons. The refractor was formally inaugurated by Emperor Franz Joseph I during the opening ceremony of the University Observatory on June 5th, 1883. In order to facilitate observations, and to make observations of objects near the horizon possible, the dome was electrified during the 1950s and a lifting platform was added.


The Small Radio Telescope (SRT)

The institute has had a small radio telescope at its disposal since 2005. Its dish antenna is 2.3 meters in diameter. This device allows for observations of the interstellar medium’s 21cm hydrogen line as well as the neighbouring continuum. Installed on the university observatory’s western terrace, it is used primarily by students during practical courses.

15-inch Double Refractor Astrograph

In the westernmost part of the observatory grounds, the dome of the historic astrograph rises on a small hill. This double telescope installed in 1911 - one for photography and a second for visual observation and tracking - enabled participation in the international photographic sky survey Carte du Ciel. The positions, proper motions and brightnesses of stars were measured and a large number of variable stars, comets and minor planets were discovered. The Carl Zeiss blink comparator, financed by Albert Freiherr von Rothschild, was used to evaluate the celestial images.

Rothschild - Coudé

To the west of the main building is the Coudé Tower donated by Albert Freiherr von Rothschild. The main instrument, which gives the building its name and is very rare worldwide, was of the Coudé type and its complicated beam path with plane mirrors behind the 38cm objective enabled a fixed and thus stable installation of heavy analytical instruments, especially the spectrograph still used in teaching. On the dedication plaque above the entrance to the building, the letters referring to the donor Rothschild in the Third Reich have been made illegible, but they are still visible in special light.