View source for National Radio Astronomy Observatory

{{Short description|Federally funded research and development center for radio astronomy}}
{{Infobox observatory
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The '''National Radio Astronomy Observatory''' ('''NRAO''') is a [[federally funded research and development center]] of the [[National Science Foundation|United States National Science Foundation]] operated under cooperative agreement by [[Associated Universities, Inc]]. for the purpose of [[radio astronomy]]. NRAO designs, builds, and operates its own high-sensitivity [[radio telescope]]s for use by scientists around the world.<ref>{{cite web|url=https://public.nrao.edu/|title=National Radio Astronomy Observatory|website=National Radio Astronomy Observatory|access-date=20 May 2019}}</ref>

==Locations==
===Charlottesville, Virginia===
The NRAO headquarters is located on the campus of the [[University of Virginia]] in [[Charlottesville, Virginia]]. The North American [[Atacama Large Millimeter Array|ALMA]] Science Center and the NRAO Technology Center and Central Development Laboratory are also in Charlottesville.<ref>{{cite web|url=https://www.nrao.edu/directions/cville/|title=Maps & Directions|website=Nrao.edu|access-date=20 May 2019}}</ref>

===Green Bank, West Virginia===
[[File:GBT.png|thumb|left|The 100-meter [[Green Bank Telescope]]]]
NRAO was, until October 2016, the operator of the world's largest fully steerable [[radio telescope]], the [[Robert C. Byrd Green Bank Telescope]], which stands near [[Green Bank, West Virginia]].<ref>{{cite web|url=https://www.aui.edu/news/nrao-structural-changes-announcing-the-separation-of-the-green-bank-observatory-and-the-long-baseline-observatory/|title=NRAO Structural Changes: Announcing the Separation of the Green Bank Observatory and the Long Baseline Observatory|website=Associated Universities, Inc.|date=29 March 2016 |access-date=May 20, 2019}}</ref> The observatory contains several other telescopes, among them the {{convert|140|ft|adj=on}} telescope that utilizes an [[equatorial mount]] uncommon for radio telescopes, three {{convert|85|ft|adj=on}} telescopes forming the [[Green Bank Interferometer]], a {{convert|40|ft|adj=on}} telescope used by school groups and organizations for small scale research, a fixed radio "[[horn (telescope)|horn]]" built to observe the radio source Cassiopeia A, as well as a reproduction of the original antenna built by [[Karl Guthe Jansky|Karl Jansky]] while he worked for Bell Labs to detect the [[Electromagnetic interference|interference]] that was discovered to be previously unknown natural [[radio waves]] emitted by the universe.<ref>{{cite web|url=http://www.gb.nrao.edu/othertelescopes.shtml|title=Other Telescopes at Green Bank|website=Gb.nrao.edu|access-date=May 20, 2019}}</ref>

Green Bank is in the [[United States National Radio Quiet Zone|National Radio Quiet Zone]], which is coordinated by NRAO for protection of the Green Bank site as well as the [[Sugar Grove Station]] monitoring site operated by the [[NSA]]. The zone consists of a {{convert|13000|mi2|adj=on}} 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]] in 1958. No fixed radio transmitters are allowed within the area closest to the telescope. 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]] 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 to block electromagnetic interference at the wavelengths used by the observatory. At one point, the observatory faced the problem of [[New World flying squirrel|North American flying squirrels]] tagged with [[United States Fish and Wildlife Service]] telemetry transmitters. Electric fences, electric blankets, faulty automobile electronics, and other radio wave emitters have caused great trouble for the astronomers in Green Bank. All vehicles on the premises are powered by diesel motors to minimize interference by ignition systems.<ref>{{cite web|url=https://science.nrao.edu/facilities/gbt/interference-protection/nrqz/|title=National Radio Quiet Zone — Science Website|website=Science.nrao.edu|access-date=May 20, 2019}}</ref><ref>{{cite web|url=http://www.gb.nrao.edu/visitors/TheEnemyIsUs.pdf|title=NRAO Green Bank Site RFI Regulations for Visitors.|website=Gb.nrao.edu|access-date=May 20, 2019}}</ref>

[[File:300ft after hi.tif|thumb|left|The 300-foot telescope after collapsing on November 15th, 1988]]
Until its collapse on November 15, 1988, a 300&nbsp;ft radio telescope<ref>{{cite web|url=https://public.nrao.edu/telescopes/300-foot-telescope/|title=300-ft telescope at Green Bank Site.|website=Gb.nrao.edu|access-date=August 17, 2022}}</ref> stood at the Green Bank Observatory's unique site. It was the largest radio telescope on Earth when it was brought online for its first observation at 12:42&nbsp;am on September 21, 1962. The telescope's first observation was of the remnants of Tycho's supernova that had exploded 11 November 1572. Two major overhauls installed a new surface in 1970 to correct for maintenance, snow damage, and warping from its sheer size; then a new, bigger project building was constructed in 1972 that incorporated a Farady cage around the control room itself. The telescope stood at 240&nbsp;ft in height, weighed 600 tons, had a 2-minute arc accuracy, and had a surface accuracy of ~1 inch. The collapse in 1988 was found to be due to unanticipated stresses which cracked a hidden, yet weight- and stress-supporting steel connector plate, in the support structure of the massive telescope. A cascade failure of the structure occurred at 9:43&nbsp;pm, causing the entire telescope to implode. The debris from the collapse was cleared by June 1989, and West Virginia [[Robert C. Byrd|Senator Robert C. Byrd]] would pioneer a campaign in Congress to replace it with the [[Green Bank Telescope]], construction for which began in 1990.

===Socorro, New Mexico===
[[File:USA.NM.VeryLargeArray.02.jpg|right|thumb|The [[Very Large Array]] (VLA), an array of 27 dish antennas]]
The NRAO's facility in [[Socorro, New Mexico|Socorro]] is the [[Pete Domenici]] [[Array Operations Center]] (AOC). Located on the [[New Mexico Tech]] university campus, the AOC serves as the headquarters for the [[Very Large Array]] (VLA), which was the setting for the [[1997 in film|1997 movie]] ''[[Contact (1997 American film)|Contact]]'', and is also the control center for the [[Very Long Baseline Array]] (VLBA). The ten VLBA telescopes are in [[Hawaii]], the [[U.S. Virgin Islands]], and eight other sites across the continental United States.<ref>{{cite web|url=http://www.aoc.nrao.edu/|title=NRAO: Socorro, New Mexico|website=Aoc.nrao.edu|access-date=20 May 2019}}</ref>

===Tucson, Arizona===
Offices were located on the [[University of Arizona]] campus. NRAO formerly operated the [[ARO 12m Radio Telescope|12-Meter Telescope]] on [[Kitt Peak]]. NRAO suspended operations at this telescope and funding was rerouted to the [[Atacama Large Millimeter Array]] (ALMA) instead.<ref>{{cite web|url=http://legacy.nrao.edu/tuc.shtml|title=National Radio Astronomy Observatory – Legacy Content – Tucson|website=Legacy.nrao.edu|access-date=20 May 2019}}</ref> The [[Arizona Radio Observatory]] now operates the 12-Meter Telescope.<ref>{{cite web|url=http://aro.as.arizona.edu/|title=Arizona Radio Observatory|website=Aro.as.arizona.edu|access-date=20 May 2019}}</ref>

===San Pedro de Atacama, Chile===
The [[Atacama Large Millimeter Array]] (ALMA) site in Chile is at ~{{cvt|5000|m}} altitude near [[Cerro Chajnantor]] in northern Chile.<ref>{{cite web|url=http://www.almaobservatory.org/|title=ALMA|website=Almaobservatory.org|access-date=20 May 2019}}</ref> This is about {{convert|40|km|abbr=in}} east of the historic village of [[San Pedro de Atacama]], {{convert|130|km|abbr=in}} southeast of the mining town of Calama, and about {{convert|275|km|abbr=in}} east-northeast of the coastal port of [[Antofagasta]].<ref>{{cite web|url=http://www.almaobservatory.org/en/about-alma/location|title=ALMA Location|website=Almaobservatory.org|access-date=20 May 2019}}</ref>
{{Wide image|Halfway There - 33 ALMA Antennas on Chajnantor.jpg|799px|On 12 May 2012, another Atacama Large Millimeter/submillimeter Array (ALMA) antenna was carried up to the 5,000-metre plateau of Chajnantor, bringing the total on the plateau to 33.<ref>{{cite news|title=Halfway There: 33 ALMA Antennas on Chajnantor|url=http://www.eso.org/public/announcements/ann12035/|access-date=15 May 2012|newspaper=ESO Announcement}}</ref>}}

==Jansky Prize==
The [[Karl Guthe Jansky|Karl G. Jansky]] Lectureship is a prestigious lecture awarded by the board of trustees of the NRAO. The Lectureship is awarded "to recognize outstanding contributions to the advancement of radio astronomy."<ref>{{cite web|url=https://www.nrao.edu/jansky/janskyprize.shtml|title=Jansky Lecture Redirect|website=Nrao.edu|access-date=20 May 2019}}</ref> Recipients have included [[Fred Hoyle]], [[Charles Townes]], [[Edward M. Purcell]], [[Subrahmanyan Chandrasekhar]], [[Philip Morrison]], [[Vera Rubin]], [[Jocelyn Bell Burnell]], [[Frank J. Low]], and Mark Reid.<ref>{{cite web|url=https://www.nrao.edu/jansky/2012/reid.shtml|title=2012 Jansky Lecturer|website=Nrao.edu|access-date=20 May 2019}}</ref> The lecture is delivered in [[Charlottesville, Virginia|Charlottesville]], [[Green Bank, West Virginia|Green Bank]], and in [[Socorro, New Mexico|Socorro]].

==See also==
*[[List of astronomical observatories]]
*[[National Optical Astronomy Observatory]]

==References==
{{Reflist|30em}}

==External links==
{{Commons category|National Radio Astronomy Observatory}}
* {{official website|http://www.nrao.edu/}}

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[[Category:Radio observatories]]
[[Category:Astronomy institutes and departments]]
[[Category:Federally Funded Research and Development Centers]]
[[Category:University of Virginia]]
[[Category:National Science Foundation]]
[[Category:Radio astronomy research institutes]]
[[Category:Research institutes in Virginia]]
[[Category:Science and technology in Virginia]]
[[Category:Research institutes established in 1956]]
[[Category:Scientific organizations established in 1956]]
[[Category:1956 establishments in Virginia]]
[[Category:Organizations based in Virginia]]