A primary mirror is the principal light-gathering surface of a reflecting telescope.
The Nice Observatory is an astronomical observatory located in Nice, France on the summit of Mount Gros. The observatory was founded in 1879, by the banker Raphaël Bischoffsheim. The architect was Charles Garnier, and Gustave Eiffel designed the main dome.
The Mount Wilson Observatory (MWO) is an astronomical observatory in Los Angeles County, California, United States. The MWO is located on Mount Wilson, a 1,740-metre (5,710-foot) peak in the San Gabriel Mountains near Pasadena, northeast of Los Angeles.
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 spy glasses 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were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures.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.
Stardome Observatory is a public astronomical observatory situated in Maungakiekie/One Tree Hill Domain in New Zealand's largest city, Auckland.
The Dominion Astrophysical Observatory, located on Observatory Hill, in Saanich, British Columbia, was completed in 1918 by the Canadian government. The Dominion Architect responsible for the building was Edgar Lewis Horwood. The main instrument is the 72 inch aperture Plaskett telescope, proposed and designed by John S. Plaskett in 1910 with the support of the International Union for Cooperation in Solar Research.
Kleť Observatory is an astronomical observatory in the Czech Republic. It is situated in South Bohemia, south of the summit of Mount Kleť, near the town of České Budějovice. Constructed in 1957, the observatory is at an altitude of 1,070 metres (3,510 ft) and has around 150 clear nights per year.
The New Greek Telescope project of the National Observatory of Athens (NOA) was funded by the European Commission and the General Secretariat for Research and Technology of the Hellenic Ministry of Development. The telescope had its first light test in 2005, and became the largest telescope in Greece when it became fully operational at the Chelmos Observatory site in 2007. The telescope is operated by the Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing (IAASARS) of the NOA. It is part of the OPTICON consortium of medium size telescopes.
The Indian Astronomical Observatory (IAO), located in Hanle near Leh in Ladakh, India, has one of the world's highest located sites for optical, infrared and gamma-ray telescopes. It is operated by the Indian Institute of Astrophysics, Bangalore. It is currently the ninth highest optical telescope in the world, situated at an elevation of 4,500 meters (14,764 ft).
The Asiago Astrophysical Observatory is an Italian astronomical observatory owned and operated by the University of Padua. Founded in 1942, it is located on the plateau of Asiago, 90 kilometers northwest of Padua, near the town of Asiago. Its main instrument is the 1.22-meter Galilei telescope, currently used only for spectrometric observations.
The Special Astrophysical Observatory of the Russian Academy of Science is an astronomical observatory, set up in 1966 in the USSR, and now operated by the Russian Academy of Sciences. Based in the Bolshoi Zelenchuk Valley of the Greater Caucasus near the village of Nizhny Arkhyz, the observatory houses the BTA-6 and RATAN-600, an optical and radio telescope, respectively. The two instruments are about 20 km (12 mi) apart.
The MMT Observatory (MMTO) is an astronomical observatory on the site of Fred Lawrence Whipple Observatory. The Whipple observatory complex is located on Mount Hopkins, Arizona, US in the Santa Rita Mountains. The observatory is operated by the University of Arizona and the Smithsonian Institution, and has a visitor center in nearby Amado, Arizona. The MMTO is the home of the MMT, which has a primary mirror 6.5 m in diameter. The name comes from the six smaller mirrors originally used before the single primary mirror was installed in 1998. The primary mirror has a special lightweight honeycomb design made by the University of Arizona's Steward Observatory Mirror Laboratory. The MMT is housed in a building which allows the walls and roof around the telescope to be completely rolled back, allowing it to cool down very quickly in order to improve observation.
The Molėtai Astronomical Observatory is an astronomical observatory owned and operated by Vilnius University Institute of Theoretical Physics and Astronomy. It is located on the Kaldiniai Hill next to Kulionys, Lithuania, 10 km from the town of Molėtai.
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.
Mount Lemmon Observatory (MLO), also known as the Mount Lemmon Infrared Observatory, is an astronomical observatory located on Mount Lemmon in the Santa Catalina Mountains approximately 28 kilometers (17 mi) northeast of Tucson, Arizona (US). The site in the Coronado National Forest is used with special permission from the U.S. Forest Service by the University of Arizona's Steward Observatory, and contains a number of independently managed telescopes.
The Llano del Hato National Astronomical Observatory is an astronomical observatory in Venezuela. It is 3600 meters above sea level and is the country's main observatory. It is situated above the village of Llano del Hato in the Venezuelan Andes, not far from Apartaderos which lies about 50 kilometers north-east of Mérida, Mérida State.
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.
A telescope is an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects, or various devices used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. The first known practical telescopes were refracting telescopes invented in the Netherlands at the beginning of the 17th century, by using glass lenses. They were used for both terrestrial applications and astronomy.
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.
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