A refracting telescope is a type of optical telescope that uses a lens as its objective to form an image. The refracting telescope design was originally used in spyglasses and astronomical telescopes but is also used for long-focus camera lenses. Although large refracting telescopes were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures. A refractor's magnification is calculated by dividing the focal length of the objective lens by that of the eyepiece.
Friedrich Simon Archenhold was an astronomer who founded the Treptow Observatory in Berlin-Treptow. He graduated from the Realgymnasium in Lippstadt before entering Friedrich Wilhelm University in 1882, where he and Wilhelm Förster founded the Urania Society at the Berlin University Observatory.
The Berlin Observatory is a German astronomical institution with a series of observatories and related organizations in and around the city of Berlin in Germany, starting from the 18th century. It has its origins in 1700 when Gottfried Leibniz initiated the "Brandenburg Society of Science″ which would later (1744) become the Prussian Academy of Sciences. The Society had no observatory but nevertheless an astronomer, Gottfried Kirch, who observed from a private observatory in Berlin. A first small observatory was furnished in 1711, financing itself by calendrical computations.
Štefánik's Observatory is an astronomical observatory on Petřín hill in the center of Prague founded 1928 and named after Slovak astronomer Milan Rastislav Štefánik. Nowadays the observatory specializes above all in popularization of astronomy and related natural sciences.
Stuttgart Observatory is an astronomical observatory owned and operated by the association Schwäbische Sternwarte e.V. It is located on the Uhlandshöhe in Stuttgart, Germany. Public tours have been held since 1920 and the observatory claims to be one of the oldest in Germany.
Hamburg Observatory is an astronomical observatory located in the Bergedorf borough of the city of Hamburg in northern Germany. It is owned and operated by the University of Hamburg, Germany since 1968, although it was founded in 1825 by the City of Hamburg and moved to its present location in 1912. It has operated telescopes at Bergedorf, at two previous locations in Hamburg, at other observatories around the world, and it has also supported space missions.
The Yale University Observatory, also known as the Leitner Family Observatory and Planetarium, is an astronomical observatory owned and operated by Yale University, and maintained for student use. It is located in Farnham Memorial Gardens near the corner of Edwards and Prospect Streets, New Haven, Connecticut.
The Royal Observatory of Belgium, has been situated in the Uccle municipality of Brussels, Belgium, since 1890. It was first established in Saint-Josse-ten-Noode in 1826 by King William I of the Netherlands under the impulse of Adolphe Quetelet. It was home to a 100 cm (39 in) diameter aperture Zeiss reflector in the first half of the 20th century, one of the largest telescopes in the world at the time. It now owns a variety of other astronomical instruments, such as astrographs, as well as a range of seismograph equipment.
Chabot Space and Science Center, located in Oakland, California, is a center for science learning featuring interactive exhibits, planetariums, a large screen theater, hands-on activities and three powerful telescopes.
The Archenhold Observatory was named in honour of Friedrich Simon Archenhold, is an observatory in Berlin-Treptow. It houses the Großer Refraktor, which is the longest pointable telescope in the world. It is also called Die Himmelskanone.
Leibniz Institute for Astrophysics Potsdam (AIP) is a German research institute. It is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory Potsdam (AOP) founded in 1874. The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. The AIP was founded in 1992, in a re-structuring following the German reunification.
The Zagreb Astronomical Observatory is the astronomical observatory located in Zagreb, the Croatian capital, and founded in 1903. It is managed by the Zagreb Astronomical Society; its main purpose is educational.
Urania Sternwarte is a public observatory in the Lindenhof quarter of Zürich, Switzerland. Its name Urania refers to the muse of astronomy in Greek mythology.
Observatory Robert A. Naef is an astronomical observatory located at Épendes, Canton of Fribourg, Switzerland at 7.13938 degrees east of Greenwich and 46.76236 degrees north latitude. Its parallax constants are : ρ sin φ' = 0.68632 and ρ cos φ' = +0.72501.
Great refractor refers to a large telescope with a lens, usually the largest refractor at an observatory with an equatorial mount. The preeminence and success of this style in observational astronomy defines an era in modern telescopy in the 19th and early 20th century. Great refractors were large refracting telescopes using achromatic lenses. They were often the largest in the world, or largest in a region. Despite typical designs having smaller apertures than reflectors, great refractors offered a number of advantages and were popular for astronomy. It was also popular to exhibit large refractors at international exhibits, and examples of this include the Trophy Telescope at the 1851 Great Exhibition, and the Yerkes Great Refractor at the 1893 World's Fair in Chicago.
The Lamont–Hussey Observatory (LHO) was an astronomical observatory owned and operated by the University of Michigan (UM). It was located in the city of Bloemfontein, Free State, South Africa. Construction at the site began in 1927, and the facility was closed in 1972.
The Public Observatory Regensburg is an astronomical observatory located in Regensburg, Germany. Its history dates back to the year 1774 when Saint Emmeram's Abbey dedicated two towers to astronomical observations. For the most time, it served for educational purposes. Today it is run by a non-profit organization, the Verein der Freunde der Sternwarte Regensburg e.V.. The observatory is accessible for visitors on Friday evenings.
The Linden Observatory Complex is a heritage-listed former observatory and manufacture of optical precision implements and now residence, museum, observatory, education facility and meeting venue located at 91 – 111 Glossop Road, Linden, City of Blue Mountains, New South Wales, Australia. It was designed and built by Ken Beames from 1938 to 1948. It is also known as K Beames Engineering Co. The property is owned by the Linden Observatory Trust. It was added to the New South Wales State Heritage Register on 5 March 2010.
The Bamberg-Refraktor is a large telescope. The refracting telescope has an aperture of 320 millimetres, a focal length of five metres and is located in the Wilhelm Foerster Observatory in the Berlin district of Schöneberg.
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