National Radio Astronomy Observatory

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The National Radio Astronomy Observatory (NRAO) is a Federally Funded Research and Development Center set up by the United States National Science Foundation for the purpose of radio astronomy. NRAO designs, builds, and operates its own high-power radio telescopes for use by scientists around the world.

Locations

NRAO headquarters is located on the University of Virginia grounds. The North American ALMA Science Center and the NRAO Technology Center are also located in Charlottesville.

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NRAO is the constructor/owner of the worlds largest fully mobile radio telescope, the Green Bank Telescope, which resides in Green Bank, West Virginia. Green Bank is the center of the United States national radio quiet zone, which NRAO is also responsible for maintaining. It resides on a 13,000 square mile piece of land void of electromagnetic pollution. The land was set aside by the Federal Communications Commission in 1958, as a Radio Quiet Zone; the area closest to the telescope is free of fixed radio transmitters, and all other fixed radio transmitters (TV and radio towers) inside the zone are required to transmit away from the telescope, often at limited power. It is hard to keep the site free of radio pollution. To aid in limiting outside interference, the surrounding area is planted with pines characterized by needles of a certain length as to 'block' electromagnetic interference at the wavelengths used by the observatory. At one point, the observatory faced the problem of North American flying squirrels tagged with US Fish & Wildlife Service telemetry transmitters. Electric fences and other radio wave emitters have caused great trouble for the astronomers in Green Bank. The observatory contains many other notable telescopes, including three 85 foot telescopes forming an interferometer array, a 40 foot telescope used by school groups and organizations for small scale research, a fixed radio 'horn' built to observe Cygnus X-1, a bunk house to facilitate these guests, as well as a reproduction of the original antenna built by Karl Jansky while he worked for Bell Labs to detect the interference that was discovered to be previously unknown natural radio waves emitted by the universe.

VLA: a 27-dish interferometer

The NRAO's facility in Socorro is the Array Operations Center (AOC). Located on the New Mexico Tech campus, the AOC serves as the headquarters for the Very Large Array (VLA), which was the setting for the movie Contact, and the control center for the Very Long Baseline Array (VLBA). VLBA telescopes are located throughout the world.

Offices are located on the University of Arizona campus. Formerly operated the 12 meter telescope on Kitt Peak. NRAO suspended operations at this telescope and funding was rerouted to the Atacama Large Millimeter Array (ALMA) instead. The University of Arizona's Steward Observatory now operates the 12 meter telescope.

The Atacama Large Millimeter Array (ALMA) site in Chile is at 5000 m altitude near Cerro Chajnantor in northern Chile. This is about 40 km east of the historic village of San Pedro de Atacama, 130 km southeast of the mining town of Calama, and about 275 km ENE of the coastal port of Antofagasta.

External link

• [NRAO National Radio Astronomy Observatory]

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