Yerkes Observatory is an astronomical observatory located in Williams Bay, Wisconsin, United States. The observatory was operated by the University of Chicago Department of Astronomy and Astrophysics from its founding in 1897 to 2020. Ownership was transferred to the non-profit Yerkes Future Foundation (YFF) in May 2020, which began restoration and renovation of the historic building and grounds. Re-opening for public tours and programming began May 27, 2022.
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were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures.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.
The Paris Observatory, a research institution of the Paris Sciences et Lettres University, is the foremost astronomical observatory of France, and one of the largest astronomical centers in the world. Its historic building is on the Left Bank of the Seine in central Paris, but most of the staff work on a satellite campus in Meudon, a suburb southwest of Paris.
The Stockholm Observatory is an astronomical observatory and institution in Stockholm, Sweden, founded in the 18th century and today part of Stockholm University. In 1931, the new Stockholm Observatory, nicknamed "Saltis", was inaugurated on the Karlsbaderberget at Saltsjöbaden, near Stockholm, and operated until 2001.
Bernhard Woldemar Schmidt was an Estonian optician. In 1930 he invented the Schmidt telescope which corrected for the optical errors of spherical aberration, coma, and astigmatism, making possible for the first time the construction of very large, wide-angled reflective cameras of short exposure time for astronomical research.
Johann Georg Repsold was a German astronomer and fireman. He began to make astronomic instruments mainly for his own use and his third son Adolf Repsold went on to establish a well-known astronomical instrument making company A & G. Repsold which later became A. Repsold and Sohne.
The Schmidt–Cassegrain is a catadioptric telescope that combines a Cassegrain reflector's optical path with a Schmidt corrector plate to make a compact astronomical instrument that uses simple spherical surfaces.
Carl Ludwig Christian Rümker was a German astronomer.
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.
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 William I 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 owns a variety of other astronomical instruments, such as astrographs, as well as a range of seismograph equipment.
Richard Reinhard Emil Schorr, was a German astronomer.
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 the 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 Mirasteilas Observatory is an astronomical observatory in Falera in the canton of Grisons in Switzerland. With its 90-centimeter telescope it is the largest publicly accessible observatory in Switzerland.
The Kuffner observatory is one of two telescope-equipped public astronomical observatories situated in Austria's capital, Vienna. It is situated in the West of the city's Ottakring district, on the slope of the Gallitzinberg at 302 m altitude. Originally a private research institution, it was converted into an educational astronomy facility after World War II as buildings and city lights had encroached to a degree that severely hampered scientific nightsky observations. Today the main tasks of the observatory consist in public education on astronomy, operating and preserving the historical equipment, and minor projects in scientific astronomy.
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 National Astronomical Observatory of Chile is an astronomical observatory owned and operated by the Department of Astronomy of the University of Chile (UCh). It is located on Cerro Calán, a hill in the commune of Las Condes. The commune is an eastern suburb of Santiago located in Santiago Province of the Santiago Metropolitan Region. OAN was founded in 1852 and became a part of UCh in 1927. The facility on Cerro Calán was completed in 1962.
The Altona Observatory was an astronomical observatory situated in the Palmaille, in Altona, Hamburg. The observatory was founded by Heinrich Christian Schumacher in 1823 and continued to operate until 1871, 21 years after his death. It closed due to funding being cut off following the cession of the 'Elbe Duchies' of Schleswig, Holstein, and Saxe-Lauenburg by Denmark to Austria and Prussia following the Second Schleswig War.
Potsdam Great Refractor is an historic astronomical telescope in an observatory in Potsdam, Germany.
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