Sonneberg observatory

from Wikipedia, the free encyclopedia
Sonneberg observatory

The Sonneberg observatory is located on the 638 m high Erbisbühl in Neufang , a district of Sonneberg . It was built in the mid-1920s on the initiative of Cuno Hoffmeister by the city of Sonneberg with the support of the Carl Zeiss Foundation . On December 28, 1925, the observation station with the first dome tower was inaugurated and expanded significantly by extensions until 1928 as the then “highest observatory in Germany”.

The astronomy museum of the observatory is open to interested visitors, especially amateur astronomers and schoolchildren, in order to familiarize them with the history and recent findings in the fields of astronomy and astrophysics in popular science events .

history

One of the Sonneberg observation domes, around 1935

From 1930 the observatory was leased to the Prussian state and thus de facto became a branch of the Berlin-Babelsberg University Observatory . Since 1938 Paul Ahnert worked for decades at the observatory. During the Second World War , the observatory was also used as an air and weather observation station from 1940 and was subordinate to the Reich Weather Service and with it the Air Force. After the war, Cuno Hoffmeister managed to continue the observatory's research programs even under Soviet occupation . However, the occupying power 1945 possessed in the course of reparations the disassembly of the most powerful telescope - a 40 cm- astrographs - for a Soviet observatory. From April 1946 the Sonneberg observatory became a research institute of the German Academy of Sciences in Berlin.

In the 1950s, the observatory was expanded extensively. Since then, it has consisted of several one to two-storey buildings, separated by green spaces, with generous laboratory and work areas and attached domes for the observation devices. By the early 1960s, many new instruments were also purchased and the number of scientific staff increased considerably. In 1960 and 1961 two astrographs, each 40 cm in diameter, were put into operation. The major investment in a 2 m Schmidt telescope (Germany's largest telescope ever), which was also discussed for Sonneberg , was finally relocated to Tautenburg near Jena in 1960 to set up a new observatory there - today's Thuringian State Observatory .

After the Wall was built in Berlin on August 13, 1961, the Sonneberg observatory was in the restricted border area and was therefore almost inaccessible for visitors and scientists who did not live within the Sonneberg restricted zone and therefore no longer presentable in international research. In the course of a reform of the Academy of Sciences, the scientific management was removed in 1967 and the facility was subordinated to the Institute for Astrophysics . Further plans for 1969 even included the dismantling of all instruments, relocation of the scientific staff and complete closure. The new scientific director, Wolfgang Wenzel , prevented this through his intervention. A ban on observation with the large instruments was initially ignored and reversed in the mid-1970s. The scientific work and the long-term research programs then continued until the end of the GDR in 1989. In 1989 the Sonneberg observatory had 36 employees.

With the reunification in 1990 , however, the most critical time began for the traditional observatory. At first it became the property of the State of Thuringia. After evaluating the research facilities in Thuringia, the Tautenburg observatory was given the unique status of a state observatory funded with public research funds on the basis of the above-mentioned 2-m Alfred Jensch telescope . The Sonneberg observatory was supposed to be closed in 1991. Thanks to the commitment of the then head of the observatory, Woldemar Götz , the closure of the institute was postponed until the end of 1994 and the observatory continued to operate as a branch of the Thuringian state observatory in Tautenburg with ten employees. In 1992, the new director of the observatory, Hans-Jürgen Bräuer , founded the friends' association “Friends of the Sonneberg Observatory eV” together with Klaus Hoffmeister, a nephew of Cuno Hoffmeister. V. “The observatory was reopened on November 9, 1995. Between 1995 and 2003 it was a municipal institution that received financial support from the city and district of Sonneberg as well as from the states of Bavaria and Thuringia. Under the direction of Constanze la Dous , a five-year project was launched with four employees to continue the internationally recognized Sonneberg sky observation programs and digitize the second largest astroplate collection in the world.

In 1998 an astronomy museum was set up in the oldest building of the observatory. In 2003 the museum had around 5000 visitors. The implementation of the project and the establishment of the museum was also made possible through the use of ABM employees. When the project ended in December 2000, it was again possible to receive funding from the district and the city in order to be able to continue working until 2002. The project was last extended to the end of 2003.

Since January 1st, 2004 the observatory has been continued by the Zweckverband Sternwarte Sonneberg and the company 4pi Systeme - Gesellschaft für Astronomie und Informationstechnologie mbH . The company, which was founded in 2000 by former employees of the Sonneberg observatory, has twelve employees (1/2004) developing software for operating astronomical telescopes. In addition, 4pi Systems, with the support of the “Friends of the Sun Mountain Observatory”, was responsible for the operator function for the scientific facilities of the observatory. The astronomy museum was run by the association so that the astronomy museum, lecture hall and the observation instruments of the observatory could be used for exhibitions, guided tours and lectures. Since the beginning of 2016, the museum and public relations have been operated by the "Astronomiemuseum eV" association.

Scientific work

The main tasks of the observatory were:

The Sonneberg observatory (still) has the second largest astroplate archive on earth, which is a valuable source of information for research on variables. It includes over 270,000 photo plates that depict the changes in the northern starry sky over more than 70 years. In addition, there are about 5000 photo plates of the southern sky in the archive, which Cuno Hoffmeister took on several expeditions in Bolivia and South Africa between 1926 and 1959. More than a quarter of all known variable stars in the Milky Way have so far been discovered with the help of the Sonneberg astro plates. Most of the recordings were taken as part of the "Sonneberger fields plan" (Field patrol) and the "Sonneberg sky surveillance" (Sky patrol). The long-term program of the “Sonneberg Field Plan” was started in 1924 by Cuno Hoffmeister and ran until 1995. The “Sonneberg Sky Monitoring” is based on Paul Guthnick's idea to monitor the entire northern starry sky using astrophotography . This program has been running since 1926 until today. Since unexposed photo plates were no longer available from 1997, the sky surveillance had to be switched to film material. The historical photo plates are available for scientific evaluations and have also been digitized since 1992. This work continues to this day and is carried out by employees of 4pi Systeme . There was also a project to significantly improve the signal-to-noise ratio of some of the already digitized photo plates using the pixonen method. This project with the Technical University of Ilmenau ran until 2005.

Instruments

The main instrument of the observatory in 1926 was initially a 135 mm refractor with various sky cameras. In 1938 an astrograph with a 400 mm objective diameter and 1600 mm objective focal length was used as the new main instrument, but it was dismantled in 1945. Today there are two Cassegrain reflecting telescopes with a diameter of 60 cm, a Schmidt telescope with a diameter of 50 cm and two astrographs with a diameter of 40 cm each. In addition to and as a long-term alternative to the sky surveillance operated with astrographs since 1926, a CCD camera has been used in conjunction with a wide-angle lens since 2002 . A MultiMega-CCD camera (manufacturer: OES - Optical and Electronic Systems) with a 7k × 4k chip (chip area: 84 × 48 mm, make Philips ) and a water-cooled Peltier element serves as the camera .

The refractor from 1926 and the 60 cm Cassegrain reflecting telescope are now available to visitors as part of public observation evenings for observing the sky.

literature

  • Cuno Hoffmeister, Gerold Richter , Wolfgang Wenzel: Variable stars. JA Barth Verlag, Leipzig 1990. ISBN 3-335-00224-5
  • Wolfgang Wenzel, Inge Häusele: Sonneberger photographic sky atlas. JA Barth Verlag, Leipzig 1991. ISBN 3-335-00297-0
  • Peter Kroll , Constanze La Dous, Hans-Jürgen Bräuer: Treasure Hunting in Astronomical Plate Archives. Proceedings of the international workshop held at Sonneberg Observatory, March 4 to 6, 1999. Herri Deutsch, Frankfurt / M. 1999. ISBN 3-8171-1599-7
  • Rainer Luthardt : Sonneberg Calendar for Star Friends. Harri Deutsch, Frankfurt / M. 1994, 1995. ISSN  0944-7679
  • Rainer Luthardt: Sonneberger yearbook for star friends. Harri Deutsch, Frankfurt a. M. 1995-2000. ISBN 3-8171-2000-1 , ISSN  1430-0141

Web links

Commons : Sonneberg Observatory  - Collection of images, videos and audio files

Coordinates: 50 ° 22 ′ 39 ″  N , 11 ° 11 ′ 24 ″  E