National Radio Astronomy Observatory
Encyclopedia
The National Radio Astronomy Observatory (NRAO) is a Federally Funded Research and Development Center of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 National Science Foundation
National Science Foundation
The National Science Foundation is a United States government agency that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National Institutes of Health...

 operated under cooperative agreement by Associated Universities, Inc
Associated Universities, Inc
Associated Universities, Inc. is a research management corporation that builds and operates facilities for the research community. AUI is a not-for-profit 501 corporation, headquartered in Washington, DC. The President and Chief Executive Officer is Ethan J. Schreier...

 for the purpose of radio astronomy
Radio astronomy
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The initial detection of radio waves from an astronomical object was made in the 1930s, when Karl Jansky observed radiation coming from the Milky Way. Subsequent observations have identified a number of...

. NRAO designs, builds, and operates its own high sensitivity radio telescope
Radio telescope
A radio telescope is a form of directional radio antenna used in radio astronomy. The same types of antennas are also used in tracking and collecting data from satellites and space probes...

s for use by scientists around the world.

Charlottesville, Virginia

NRAO headquarters is located on the University of Virginia
University of Virginia
The University of Virginia is a public research university located in Charlottesville, Virginia, United States, founded by Thomas Jefferson...

 grounds. The North American ALMA
ALMA
ALMA can refer to* ALMA Award, a distinction awarded to Latino performers who promote positive portrayals of Latinos in the entertainment field.* ALMA Magazine, a Spanish-language lifestyle magazine....

 Science Center and the NRAO Technology Center are also located in Charlottesville. This site is the workplace of nearly 100 scientists, including J. Richard Fisher
J. Richard Fisher
J. Richard Fisher is an astronomer at the National Radio Astronomy Observatory at Charlottesville, VA. He received his Ph.D. in Astronomy from the University of Maryland, College Park and his B.S. in Physics from the Pennsylvania State University.Fisher, along with R...

 and Jeffrey Mangum.

Green Bank, West Virginia

NRAO is the operator of the world's largest fully steerable radio telescope
Radio telescope
A radio telescope is a form of directional radio antenna used in radio astronomy. The same types of antennas are also used in tracking and collecting data from satellites and space probes...

, the Green Bank Telescope
Green Bank Telescope
The Robert C. Byrd Green Bank Telescope is the world's largest fully steerable radio telescope and the world's largest land-based movable structure. It is part of the National Radio Astronomy Observatory site at Green Bank, West Virginia, USA. The telescope honors the name of the late Senator...

, which stands near Green Bank, West Virginia. The observatory contains many other notable telescopes, among them the 140 feet (42.7 m) telescope that utilizes an equatorial mount
Equatorial mount
An equatorial mount is a mount for instruments that follows the rotation of the sky by having one rotational axis parallel to the Earth's axis of rotation. This type of mount is used for astronomical telescopes and cameras...

 uncommon for radio telescopes, three 85 feet (25.9 m) telescopes forming the Green Bank Interferometer
Green Bank Interferometer
The Green Bank Interferometer is a former radio astronomy telescope located at Green Bank, West Virginia and operated by the National Radio Astronomy Observatory...

, a 40 feet (12.2 m) telescope used by school groups and organizations for small scale research, a fixed radio 'horn
Horn (telescope)
A horn is a stationary radio telescope. Horns were originally built to observe specific objects in the sky, and preceded the more commonly known movable dishes used today.-See also:* Feed horn* Horn...

' built to observe Cygnus X-1
Cygnus X-1
Cygnus X-1 is a well-known galactic X-ray source in the constellation Cygnus. It was discovered in 1964 during a rocket flight and is one of the strongest X-ray sources seen from Earth, producing a peak X-ray flux density of 2.3 Wm−2Hz−1...

, a bunk house to facilitate these guests, as well as a reproduction of the original antenna built by Karl Jansky
Karl Guthe Jansky
Karl Guthe Jansky was an American physicist and radio engineer who in August 1931 first discovered radio waves emanating from the Milky Way. He is considered one of the founding figures of radio astronomy.- Early life :...

 while he worked for Bell Labs to detect the interference
Electromagnetic interference
Electromagnetic interference is disturbance that affects an electrical circuit due to either electromagnetic induction or electromagnetic radiation emitted from an external source. The disturbance may interrupt, obstruct, or otherwise degrade or limit the effective performance of the circuit...

 that was discovered to be previously unknown natural radio waves
Radio waves
Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. Radio waves have frequencies from 300 GHz to as low as 3 kHz, and corresponding wavelengths from 1 millimeter to 100 kilometers. Like all other electromagnetic waves,...

 emitted by the universe.

Green Bank is in the United States National Radio Quiet Zone
United States National Radio Quiet Zone
The United States National Radio Quiet Zone is a large area of land surrounding the National Radio Astronomy Observatory at Green Bank, West Virginia, and especially the large Green Bank Telescope radio telescope. The Radio Quiet Zone is a rectangle of land approximately in size that straddles...

, which is coordinated by NRAO for protection of the Green Bank site as well as the Sugar Grove, West Virginia
Sugar Grove, West Virginia
Sugar Grove is an American government communications site located in Pendleton County, West Virginia operated by the National Security Agency. According to a in the New York Times, the site intercepts all international communications entering the Eastern United States.The site was first developed...

 monitoring site operated by the National Security Agency
National Security Agency
The National Security Agency/Central Security Service is a cryptologic intelligence agency of the United States Department of Defense responsible for the collection and analysis of foreign communications and foreign signals intelligence, as well as protecting U.S...

. The zone consists of a 13000 square miles (33,669.8 km²) piece of land where fixed transmitters must coordinate their emissions before a license is granted. The land was set aside by the Federal Communications Commission
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...

 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 including TV and radio towers inside the zone are required to transmit such that interference at the antennas is minimized by methods including limited power and using highly directional antennas. With the advent of wireless
Wireless
Wireless telecommunications is the transfer of information between two or more points that are not physically connected. Distances can be short, such as a few meters for television remote control, or as far as thousands or even millions of kilometers for deep-space radio communications...

 technology and microprocessors in everything from cameras to cars it is difficult to keep the sites free of radio interference. To aid in limiting outside interference, the area surrounding the Green Bank observatory was at one time 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
New World flying squirrel
The two species of New World flying squirrels, genus Glaucomys, are the only species of flying squirrel found in North America. They are distributed from Alaska to Honduras. They are similar in many ways to the Eurasian flying squirrels in the genus Pteromys...

 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.

Socorro, New Mexico

The NRAO's facility in Socorro is the Array Operations Center
Array Operations Center
The Array Operations Center in Socorro, New Mexico, is the control and monitor centre for the VLBA and the VLA. From the AOC, NRAO operators are able to remotely control and monitor the remote stations over the internet. The operators can aim the antennas, select radio frequencies for observation,...

 (AOC). Located on the New Mexico Tech campus, the AOC serves as the headquarters for the Very Large Array
Very Large Array
The Very Large Array is a radio astronomy observatory located on the Plains of San Agustin, between the towns of Magdalena and Datil, some fifty miles west of Socorro, New Mexico, USA...

 (VLA), which was the setting for the movie Contact, and the control center for the Very Long Baseline Array
Very Long Baseline Array
The Very Long Baseline Array is a system of ten radio telescopes controlled remotely from the Array Operations Center in Socorro, New Mexico by the National Radio Astronomy Observatory. The array works together as the world's largest dedicated, full-time astronomical instrument using the...

 (VLBA). VLBA telescopes are located in Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

, the United States Virgin Islands
United States Virgin Islands
The Virgin Islands of the United States are a group of islands in the Caribbean that are an insular area of the United States. The islands are geographically part of the Virgin Islands archipelago and are located in the Leeward Islands of the Lesser Antilles.The U.S...

, and several sites across the continental United States

Tucson, Arizona

Offices are located on the University of Arizona
University of Arizona
The University of Arizona is a land-grant and space-grant public institution of higher education and research located in Tucson, Arizona, United States. The University of Arizona was the first university in the state of Arizona, founded in 1885...

 campus. NRAO formerly operated the 12 Meter Telescope
ARO 12m Radio Telescope
The ARO 12m Radio Telescope is a 12-meter dish located on Kitt Peak, approximately 60 mi from Tucson, Arizona at an elevation of 6215.8 ft .-History:...

 on Kitt Peak
Kitt Peak
Kitt Peak is a mountain in the U.S. state of Arizona. It is the location of the Kitt Peak National Observatory. The radio telescope at the Observatory is one of ten dishes comprising the Very Long Baseline Array ....

. NRAO suspended operations at this telescope and funding was rerouted to the Atacama Large Millimeter Array
Atacama Large Millimeter Array
The Atacama Large Millimeter/sub-millimeter Array is an array of radio telescopes in the Atacama desert of northern Chile. Since a high and dry site is crucial to millimeter wavelength operations, the array is being constructed on the Chajnantor plateau at 5000 metres altitude...

 (ALMA) instead. The Arizona Radio Observatory
Arizona Radio Observatory
The Arizona Radio Observatory , a part of Steward Observatory at the University of Arizona, operates the 12 Meter Telescope on Kitt Peak and the Submillimeter Telescope on Mount Graham....

 now operates the 12 Meter Telescope.

Santiago, Chile

The Atacama Large Millimeter Array
Atacama Large Millimeter Array
The Atacama Large Millimeter/sub-millimeter Array is an array of radio telescopes in the Atacama desert of northern Chile. Since a high and dry site is crucial to millimeter wavelength operations, the array is being constructed on the Chajnantor plateau at 5000 metres altitude...

 (ALMA) site in Chile is at ~5000 m (~16,500 ft) altitude near Cerro Chajnantor in northern Chile. This is about 40 km (about 25 miles) east of the historic village of San Pedro de Atacama
San Pedro de Atacama
San Pedro de Atacama is a Chilean town and commune in El Loa Province, Antofagasta Region. It is located east of Antofagasta, some 106 km southeast of Calama and the Chuquicamata copper mine, overlooking the Licancabur volcano. It features a significant archeological museum, the R. P...

, 130 km (about 80 miles) southeast of the mining town of Calama, and about 275 km (about 170 miles) east-northeast of the coastal port of Antofagasta
Antofagasta
Antofagasta is a port city in northern Chile, about north of Santiago. It is the capital of Antofagasta Province and Antofagasta Region. According to the 2002 census, the city has a population of 296,905...

.

External links

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