Main Building of the Tartu Observatory.
|Established||1810, 1964 (relocation)|
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The Tartu Observatory (Estonian: Tartu Observatoorium) is the largest astronomical observatory in Estonia. It is located on the Tõravere hill, about 20 km south-west of Tartu in Nõo Parish, Tartu County. The old Tartu Observatory is known internationally for its connection to Friedrich Georg Wilhelm von Struve and the Struve Geodetic Arc, of which it is the first reference point.
The Tartu Observatory was founded at the Imperial University of Dorpat as it was reopened in 1802. The observatory building was completed in 1810 on the Toome hill in Dorpat. The instruments were installed in 1814 by von Struve who subsequently started observations. In 1824, a 9" Fraunhofer refractor arrived, the largest achromatic telescope in the world at the time. When von Struve began assembling his Geodetic Arc in 1816, the doorstep of the observatory became its first point.
In 1946 the renamed Tartu Observatory was separated from the university and subjected to the Estonian Academy of Sciences. The authorities started to look for the new observational base in 1950. A patch of land on the Tõravere hill was assigned for the purpose and in 1958 construction began. By 1963, the new observatory building was completed, part of the astronomers from the old observatory moved in, and the 50 cm reflector telescope had first light. In 1964, an international conference was held and the Tartu Observatory was renamed von Struve Observatory. In 1974 the 1.5 metre telescope become operational. The name of the observatory was reverted back to Tartu Observatory in 1995. In 1998, a 0.6 metre reflector was installed, the last major instrument update for today. The old observatory building now mainly serves as a museum and is a part of a public science education centre.
The observatory has two main telescopes. The 1.5 metre Cassegrain reflector, which is the largest optical telescope in Northern Europe, is used for spectroscopic observations. The second telescope is a 0.6 metre reflector for photometric observations. There is also a pitch for a collection of meteorological instruments on the observatory grounds.
 Notes on the text
- Tartu Observatoorium 1805-1948, Georgi Želnin, 2004
- Timeline of Tartu Observatory
- Fraunhofer refractor
- About the search for dark matter in the Tartu observatory