Hamburg Observatory

Stintfang (1802–1811) The precursor of Hamburg Observatory was a quasi-private observatory by Johann Georg Repsold built in 1802, originally located at the Stintfang in Hamburg. It was built in the city with permission of the Congress. First director became Charles Rümker who had accompanied Thomas Brisbane to build the first Australian observatory at Parramatta. Christian August Friedrich Peters became assistant director in 1834. In 1856 Rümker's son George became director of the observatory. In 1854 Carl Rumaker won the Gold Medal from the Royal Society for year, for his 1852 Star catalog, which had the positions of 12000 stars. Two new instruments for the Bergedorf location were the 60 cm (~23.6 inch) aperture Great Refractor by Reposold, and Meridian Circle. One unique feature of Hamburg Great Refractor is an Iris control that allows the aperture to be adjusted from 5 to 60 cm. Two lens were produced by Steinheil, one for photography and another for visual observing, both delivered in the early 1910s. Catalogs include the AGK3-Sternkatalog (completed over 1956-1964) In 1968 the observatory became part of Hamburg University. In 1979 a small museum to Bernard Schmidt was inaugurated. In 2019, the Great Refractor building was re-open in June after it was modernized. == 1-meter reflector ==

The 1 meter reflector at Hamburg Observatory was the largest by aperture in Germany, and one of the largest in Europe, and was also among the largest telescopes of any type in the World at that time. ;Largest telescopes (all types) in 1911) Note that the prevailing glass mirror technology at this time was silver-coated glass, not vapour-deposited aluminium which did not debut until several decades later. Speculum metal mirror reflected something like 2/3 of the light, and the lens telescopes were popular for their virtues but had enormous and expensive domes due to their long focal length (also they had issues with chromatic aberration that were solved in a different way by reflecting designs). == Telescopes ==

;Telescopes • The Great Refractor, a great refractor telescope with an objective diameter (60 cm) and focal length (9 m). By Repsold, and with optics from Steinheil. (The observatory's Großer Refraktor) • The Equatorial, a refractor with aperture of 26 cm and focal length. Built in the 1870s and moved to Bergedorf. • Salvador Mirror, a Cassegrain with 8 m focal length and 40 cm mirror. • The Meridian Circle, a meridian circle built in 1907. (by A. Repsold & Söhne) • Lippert Telescope, three astrographs refractors on one mount. Built by Carl Zeiss, funded by Eduard Lippert • 1 Meter Reflector Telescope, activated in 1911. By Carl Zeiss. The largest telescope in Germany from 1911 to 1920 • Astrograph, with 8.5 cm objective, focal length 2.06 m. Built in 1924. • The aforementioned Schmidt was moved to Calar Alto Observatory in 1976. Some work was done with data from Effelsberg • The HRT telescope has been installed in March 2013 in Guanajuato, Mexico at the LaLuz Observatory of the University of Guanajuato. It is now in successful operation under its new name TIGRE. The costs and observing time are shared according to a trilateral agreement between the Universities of Liege, Guanajuato and Hamburg, the latter still leading the effort. == People of Hamburg Observatory ==

Directors of the Observatory: • Johann Georg Repsold (from 1802–1830) • Christian Karl Ludwig Rümker (director from 1833–1857) • George Rümker (director from 1857–1900) • Richard Schorr (1900–1941) • Otto Heckmann (1941–1968) 1962 became 1st head of the newly formed European Southern Observatory • Alfred Behr (1968–1979) • Co-Director with Behr: (1969–1992) In 1928, Kasimir Graff made many observations at Hamburg until he left for the Vienna Observatory. In 2009, South African pop star, singer and composer Ike Moriz filmed a music video called 'Starry Night' both inside and outside the observatory buildings. It features the Equatorial refractor telescope as well as the library and garden areas. He also sang at the 100th anniversary exhibition 'Vision Sternwarte'. == Association ==

Due to the difficult economic situation of the observatory, the "Förderverein Hamburger Sternwarte e.V." was founded in 1998. The goals of the association are primarily to preserve the buildings and astronomical equipment of the observatory in accordance with the preservation order. In addition, it does public relations work and aims to open up parts of the site to the public in the future. The application for a World Heritage Site, which has been running since 2012, is an important focus of their work. == See also ==