The Kitt Peak National Observatory (KPNO) is a United States astronomical observatory located on Kitt Peak of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono O'odham Nation, 88 kilometers (55 mi) west-southwest of Tucson, Arizona. With more than twenty optical and two radio telescopes, it is one of the largest gatherings of astronomical instruments in the northern hemisphere.
Yerkes Observatory is an astronomical observatory located in Williams Bay, Wisconsin, U.S.A. It 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 visits and programming is expected in 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were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures.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 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.
Markree Observatory was an astronomical observatory in County Sligo, Ireland. The asteroid 9 Metis was discovered from this observatory in 1848 by Cooper's assistant Andrew Graham using a comet seeker telescope. The observatory was also home to the largest refractor of the early 1830s, which had a 13.3-inch (340 mm) aperture Cauchoix of Paris lens; the largest in the world at that time. The observatory also housed a number of instruments and was operated to varying degrees throughout the 19th century.
Meyer–Womble Observatory (MWO) is an astronomical observatory owned and operated by the University of Denver. It is located near the summit of Mount Evans in the Arapaho National Forest approximately 60 kilometers (37 mi) west of Denver, Colorado (USA). At an elevation of 4,326 meters (14,193 ft), it is the third-highest optical/infrared observatory in the world, and was the highest until the Indian Astronomical Observatory opened in 2001.
The Leander McCormick Observatory is one of the astronomical observatories operated by the Department of Astronomy of the University of Virginia and is situated just outside Charlottesville, Virginia (US) in Albemarle County on the summit of Mount Jefferson. It is named for Leander J. McCormick (1819–1900), who provided the funds for the telescope and observatory.
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.
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.
Fuertes Observatory is an astronomical observatory located on the North Campus of Cornell University in Ithaca, New York. The observatory was designed by L.P. Burnham, Cornell Professor of Architecture and completed in fall of 1917. It was originally used by the Civil Engineering Department as an instructional field office for navigation and surveying. Today, the observatory is primarily used for public outreach, welcoming over two thousand visitors per year with open houses on clear Friday nights.
The Crossley telescope is a 36-inch (910 mm) reflecting telescope located at Lick Observatory in the U.S. state of California. It was used between 1895 to 2010, and was donated to the observatory by Edward Crossley, its namesake.
The Dearborn Observatory is an astronomical observatory located on the Evanston campus of Northwestern University. The observatory was originally constructed in 1888, through an agreement between the university and the Chicago Astronomical Society. In the summer of 1939, Dearborn Observatory had to be moved to make way for the construction of the Technological Institute.
McMillin Observatory was an astronomical observatory built around 1895 on the campus of Ohio State University. Named after Emerson McMillin and operated by the university, the observatory closed in 1968 and its telescope later moved to Ballreich Observatory. The observatory was equipped with photographic cameras, a filar micrometer, and a custom Brashear spectroscope. The observatory had two main focuses, education and at least one astronomic scientific research study focus.
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.
Herbert Alonzo Howe was an American astronomer and educator.
Yerkes 41-inch reflector is a 40-inch aperture (101.6 cm) reflecting telescope at the Yerkes Observatory, that was completed in 1968. It is known as the 41 inch to avoid confusion with a 40 inch refractor at the observatory. Optically it is a Ritchey–Chrétien design, and the main mirror uses low expansion glass. The telescope was used as a testbed for an adaptive optics system in the 1990s.
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