The National Optical Astronomy Observatory was formed in 1982 to consolidate all AURA-managed ground-based astronomical observatories (Kitt Peak National Observatory, Cerro Tololo Inter-American Observatory, and the National Solar Observatory with facilities at Sacramento Peak, New Mexico and Kitt Peak, Arizona) under a single Director. Today, NOAO also represents the US astronomical community in the International Gemini Project. NOAO's purpose is to provide the best ground-based astronomical telescopes to the nation's astronomers, to promote public understanding and support of science, and to advance all aspects of US ground based astronomical research. As a national facility, NOAO telescopes are open to all astronomers regardless of institutional affiliation. NOAO is funded by the National Science Foundation and operated by the Association of Universities for Research in Astronomy, Inc. NOAO has its headquarters in Tucson, AZ.

The Space Telescope Science Institute (STScI) is the astronomical research center responsible for operating the Hubble Space Telescope as an international observatory.

The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

The Observatoire de Haute-Provence (OHP) was created in 1937 as a national facility for French astronomers although the first plans for a privately financed observatory date from as early as 1923. The first astronomical observations were made in 1943 with the 1.20m telescope and the first research paper dates from 1944. The facilities were made available for foreign visiting astronomers in 1949. The Observatory is owned by the Centre National de la Recherche Scientifique (CNRS) and is funded by the CNRS and the Institut National des Sciences de l'Univers (INSU).

" Those who see the Arecibo radio telescope for the first time are astounded by the enormousness of the reflecting surface, or radio mirror. The huge "dish" is 305 m (1000 feet) in diameter, 167 feet deep, and covers an area of about twenty acres. The surface is made of almost 40,000 perforated aluminum panels, each measuring about 3 feet by 6 feet, supported by a network of steel cables strung across the underlying karst sinkhole. It is a spherical (not parabolic) reflector.
Suspended 450 feet above the reflector is the 900 ton platform. Similar in design to a bridge, it hangs in midair on eighteen cables, which are strung from three reinforced concrete towers. One is 365 feet high, and the other two are 265 feet high. All three tops are at the same elevation. The combined volume of reinforced concrete in all three towers is 9,100 cubic yards. Each tower is back-guyed to ground anchors with seven 3.25 inch diameter steel bridge cables. Another system of three pairs of cables runs from each corner of the platform to large concrete blocks under the reflector. They are attached to giant jacks which allow adjustment of the height of each corner with millimeter precision..." more