United States National Radio Quiet Zone

United States National Radio Quiet Zone
The National Radio Quiet Zone spans West Virginia, Virginia, and a small part of Maryland.

The United States National Radio Quiet Zone is a large area of land surrounding the National Radio Astronomy Observatory (NRAO) at Green Bank, West Virginia, and especially the large Green Bank Telescope radio telescope. The Radio Quiet Zone is a rectangle of land approximately 13,000 square miles (34,000 km2) in size that straddles the border area of Virginia and West Virginia. It includes all land with latitudes between 37.5°N and 39.25°N and longitudes between 78.5°W and 80.5°W. This area was chosen because it has a hilly topography that screens out most incoming radio signals, allowing the Green Bank telescopes to receive signals that are otherwise too low in power to be heard over the normal radio background in North America.

The National Radio Quiet Zone also protects the antennas and receivers of the U.S. Navy Information Operations Command (NIOC) at Sugar Grove, West Virginia.[1] The NIOC at Sugar Grove has long been the location of electronic intelligence gathering systems, and is today said to be a key station in the ECHELON system operated by the National Security Agency (NSA).[2]

The Radio Quiet Zone was established by the Federal Communications Commission (FCC) in 1958 to protect the observatory's radio telescopes from harmful interference. Omnidirectional and high-power transmissions are very restricted. Furthermore, fixed radio links are often built as tight-beamed directional links that do not illuminate the sensitive radio telescopes and electronic intelligence-gathering stations there.

Not all radio transmissions are prohibited in the Radio Quiet Zone. For example Citizen's Band radios, police and ambulance radios, and fire department radios are used there. However, large radio transmitter owners must typically coordinate their operations with representatives of the National Radio Astronomy Observatory and the U.S. Department of Defense. The Allegheny Mountain Radio company operates the only broadcast radio stations in the inner core of the Quiet Zone, with just one station in the AM band, and several low-power FM stations. Most radio transmitters within the area are licensed by the FCC (just as they are in the rest of the United States). Exceptions to the Radio Quiet Zone restrictions are usually determined on a case-by-case basis, with preference given to public safety concerns, such as remote alarm systems, repeaters for first responders, and NOAA Weather Radio. Due to the restrictions, the area has attracted people who believe they suffer from Electromagnetic hypersensitivity.[3]


Counties inside the Zone



West Virginia

Cities inside the Zone


West Virginia

Clarksburg, West Virginia, and Lynchburg, Virginia, are just outside the Quiet Zone.


  1. ^ Beaudet, Carla (1 November 2010). "National Radio Quiet Zone". Charlottesville, VA, USA: National Radio Astronomy Observatory (NRAO). http://www.gb.nrao.edu/nrqz/nrqz.shtml. Retrieved 14 September 2011. 
  2. ^ "Interception Capabilities 2000, Sugar Grove, Virginia - COMSAT interception at ECHELON site". Interception of Communications Section. Leeds, UK: Cyber-Rights & Cyber-Liberties (UK). May 11, 1999. Archived from the original on May 30, 2008. http://www.fas.org/irp/eprint/ic2000/ic2000.htm#_Toc448565544. Retrieved September 14, 2011. "Interception Capabilities 2000 Report to the Director General for Research of the European Parliament (Scientific and Technical Options Assessment programme office) on the development of surveillance technology and risk of abuse of economic information." 
  3. ^ O'Brien, Jane; Danzico, Matt (September 12, 2011). "'Wi-fi refugees' shelter in West Virginia mountains". BBC News. http://www.bbc.co.uk/news/world-us-canada-14887428. Retrieved September 13, 2011. 

External links

Coordinates: 38°22′30″N 79°30′00″W / 38.375°N 79.5°W / 38.375; -79.5

Wikimedia Foundation. 2010.

Нужна курсовая?

Look at other dictionaries:

  • United States National Radio Quiet Zone — 38° 22′ 30″ N 79° 30′ 00″ W / 38.375, 79.5 La United States …   Wikipédia en Français

  • National Radio Astronomy Observatory — (NRAO) Logo of the National Radio Astronomy Observatory (NRAO) Formation 17 November 1956 [1] Purpose/focus To provide a full range of radio telescope facil …   Wikipedia

  • Zone américaine de tranquilité radio — United States National Radio Quiet Zone La United States National Radio Quiet Zone (traduction littérale : Zone américaine nationale de silence radio) est une vaste zone entourant l Observatoire de Green Bank. C est un rectangle d environ… …   Wikipédia en Français

  • United States — a republic in the N Western Hemisphere comprising 48 conterminous states, the District of Columbia, and Alaska in North America, and Hawaii in the N Pacific. 267,954,767; conterminous United States, 3,022,387 sq. mi. (7,827,982 sq. km); with… …   Universalium

  • Radio silence — For the album by Boris Grebenshchikov, see Radio Silence. : For the song by Thomas Dolby, see The Golden Age of Wireless. In telecommunications, radio silence is a status in which all fixed or mobile radio stations in an area stop transmitting.… …   Wikipedia

  • UNITED STATES OF AMERICA — UNITED STATES OF AMERICA, country in N. America. This article is arranged according to the following outline: introduction Colonial Era, 1654–1776 Early National Period, 1776–1820 German Jewish Period, 1820–1880 East European Jewish Period,… …   Encyclopedia of Judaism

  • United States intervention in Chile — The United States intervention in Chilean politics started during the War of Chilean Independence. The influence of the United States of America in both the economic and the political arenas of Chile has gradually increased over the almost two… …   Wikipedia

  • Allegheny Mountain Radio — Infobox Radio station name = Allegheny Mountain Radio city = area = branding = Allegheny Mountain Radio slogan = The Small Station with the Big Sound airdate = frequency = format = Full Service power = erp = haat = class = facility id =… …   Wikipedia

  • List of regions of the United States — This list is incomplete; you can help by expanding it. The four United States Census Bureau regions separated by color, with the nine divisions further separated by shading. Main article …   Wikipedia

  • Military history of the United States during World War II — American B 17 Flying Fortresses in flight over Europe …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”