National Radio Astronomy Observatory

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National Radio Astronomy Observatory
Alternative namesNRAO  OOjs UI icon edit-ltr-progressive.svg
LocationUnited States
Coordinates 38°02′12″N78°31′05″W / 38.0368°N 78.5181°W / 38.0368; -78.5181 Coordinates: 38°02′12″N78°31′05″W / 38.0368°N 78.5181°W / 38.0368; -78.5181
Established1959  OOjs UI icon edit-ltr-progressive.svg
Website OOjs UI icon edit-ltr-progressive.svg
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Location of National Radio Astronomy Observatory
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The National Radio Astronomy Observatory (NRAO) is a federally funded research and development center of the 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 telescopes for use by scientists around the world. [1]



Charlottesville, Virginia

The NRAO headquarters is located on the campus of the University of Virginia in Charlottesville, Virginia. The North American ALMA Science Center and the NRAO Technology Center and Central Development Laboratory are also in Charlottesville. [2]

Green Bank, West Virginia

The 100-meter Green Bank Telescope GBT.png
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. [3] The observatory contains several other telescopes, among them the 140-foot (43 m) telescope that utilizes an equatorial mount uncommon for radio telescopes, three 85-foot (26 m) telescopes forming the Green Bank Interferometer, a 40-foot (12 m) telescope used by school groups and organizations for small scale research, a fixed radio "horn" built to observe the radio source Cassiopeia A, 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. [4]

Green Bank is in the 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 13,000-square-mile (34,000 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 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 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. [5] [6]

The 300-foot telescope after collapsing on November 15th, 1988 300ft after hi.tif
The 300-foot telescope after collapsing on November 15th, 1988

Until its collapse on November 15th, 1988, a 300ft radio telescope [7] 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 12:42am on September 21st, 1962. The telescope's first observation was of the remnants of Tycho's supernova that had exploded 11th 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 240ft in height, wieghed 600-tons, had a 2-min 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 9:43pm causing the entire telescope to implode. The debris from the collapse was cleared by June 1989, and West Virginia 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

The Very Large Array (VLA), an array of 27 dish antennas USA.NM.VeryLargeArray.02.jpg
The Very Large Array (VLA), an array of 27 dish antennas

The NRAO's facility in 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 movie 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. [8]

Tucson, Arizona

Offices were located on the University of Arizona campus. NRAO 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. [9] The Arizona Radio Observatory now operates the 12-Meter Telescope. [10]

San Pedro de Atacama, Chile

The Atacama Large Millimeter Array (ALMA) site in Chile is at ~5,000 m (16,000 ft) altitude near Cerro Chajnantor in northern Chile. [11] This is about 40 km (25 miles) east of the historic village of San Pedro de Atacama, 130 km (81 miles) southeast of the mining town of Calama, and about 275 km (171 miles) east-northeast of the coastal port of Antofagasta. [12]

Halfway There - 33 ALMA Antennas on Chajnantor.jpg
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. [13]

Jansky Prize

The 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." [14] 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. [15] The lecture is delivered in Charlottesville, Green Bank, and in Socorro.

See also

Related Research Articles

<span class="mw-page-title-main">Radio telescope</span> Directional radio antenna used in radio astronomy

A radio telescope is a specialized antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency portion of the electromagnetic spectrum emitted by astronomical objects, just as optical telescopes are the main observing instrument used in traditional optical astronomy which studies the light wave portion of the spectrum coming from astronomical objects. Unlike optical telescopes, radio telescopes can be used in the daytime as well as at night.

<span class="mw-page-title-main">Radio astronomy</span> Subfield of astronomy that studies celestial objects at radio frequencies

Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation coming from the Milky Way. Subsequent observations have identified a number of different sources of radio emission. These include stars and galaxies, as well as entirely new classes of objects, such as radio galaxies, quasars, pulsars, and masers. The discovery of the cosmic microwave background radiation, regarded as evidence for the Big Bang theory, was made through radio astronomy.

<span class="mw-page-title-main">Karl Guthe Jansky</span> American physicist and radio engineer

Karl Guthe Jansky was an American physicist and radio engineer who in April 1933 first announced his discovery of radio waves emanating from the Milky Way in the constellation Sagittarius. He is considered one of the founding figures of radio astronomy.

<span class="mw-page-title-main">Very Large Array</span> Radio astronomy observatory located in New Mexico, United States

The Karl G. Jansky Very Large Array (VLA) is a centimeter-wavelength radio astronomy observatory located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes deployed in a Y-shaped array and all the equipment, instrumentation, and computing power to function as an interferometer. Each of the massive telescopes is mounted on double parallel railroad tracks, so the radius and density of the array can be transformed to adjust the balance between its angular resolution and its surface brightness sensitivity. Astronomers using the VLA have made key observations of black holes and protoplanetary disks around young stars, discovered magnetic filaments and traced complex gas motions at the Milky Way's center, probed the Universe's cosmological parameters, and provided new knowledge about the physical mechanisms that produce radio emission.

<span class="mw-page-title-main">Green Bank Telescope</span> Radio telescope in Green Bank, WV, US

The Robert C. Byrd Green Bank Telescope (GBT) in Green Bank, West Virginia, US is the world's largest fully steerable radio telescope, surpassing the Effelsberg 100-m Radio Telescope in Germany. The Green Bank site was part of the National Radio Astronomy Observatory (NRAO) until September 30, 2016. Since October 1, 2016, the telescope has been operated by the independent Green Bank Observatory. The telescope's name honors the late Senator Robert C. Byrd who represented West Virginia and who pushed the funding of the telescope through Congress.

<span class="mw-page-title-main">Grote Reber</span> American astronomer

Grote Reber was an American pioneer of radio astronomy, which combined his interests in amateur radio and amateur astronomy. He was instrumental in investigating and extending Karl Jansky's pioneering work, and conducted the first sky survey in the radio frequencies.

<span class="mw-page-title-main">Very Long Baseline Array</span> Observatory

The Very Long Baseline Array (VLBA) is a system of ten radio telescopes which are operated remotely from their Array Operations Center located in Socorro, New Mexico, as a part of the National Radio Astronomy Observatory (NRAO). These ten radio antennas work together as an array that forms the longest system in the world that uses very long baseline interferometry. The longest baseline available in this interferometer is about 8,611 kilometers (5,351 mi).

<span class="mw-page-title-main">Atacama Large Millimeter Array</span> 66 radio telescopes in the Atacama Desert of northern Chile

The Atacama Large Millimeter/submillimeter Array (ALMA) is an astronomical interferometer of 66 radio telescopes in the Atacama Desert of northern Chile, which observe electromagnetic radiation at millimeter and submillimeter wavelengths. The array has been constructed on the 5,000 m (16,000 ft) elevation Chajnantor plateau - near the Llano de Chajnantor Observatory and the Atacama Pathfinder Experiment. This location was chosen for its high elevation and low humidity, factors which are crucial to reduce noise and decrease signal attenuation due to Earth's atmosphere. ALMA provides insight on star birth during the early Stelliferous era and detailed imaging of local star and planet formation.

<span class="mw-page-title-main">United States National Radio Quiet Zone</span> Specific land area in which radio transmissions are heavily restricted

The National Radio Quiet Zone (NRQZ) is a large area of land in the United States designated as a radio quiet zone, in which radio transmissions are heavily restricted by law to facilitate scientific research and the gathering of military intelligence. Roughly half of the zone is located in the Blue Ridge Mountains of west-central Virginia while the other half is the Allegheny Mountains of east-central West Virginia; a small part of the zone is in the southernmost tip of the Maryland panhandle.

James Richard Fisher is a scientist at the National Radio Astronomy Observatory at Charlottesville, Virginia. He received his Ph.D. in Astronomy in 1972 from the University of Maryland, College Park and his B.S. in Physics in 1965 from the Pennsylvania State University, University Park.

<span class="mw-page-title-main">Submillimetre astronomy</span> Astronomy with terahertz (< 1 mm)-range light

Submillimetre astronomy or submillimeter astronomy is the branch of observational astronomy that is conducted at submillimetre wavelengths of the electromagnetic spectrum. Astronomers place the submillimetre waveband between the far-infrared and microwave wavebands, typically taken to be between a few hundred micrometres and a millimetre. It is still common in submillimetre astronomy to quote wavelengths in 'microns', the old name for micrometre.

<span class="mw-page-title-main">Atacama Pathfinder Experiment</span> Radio telescope in the Atacama desert, northern Chile

The Atacama Pathfinder Experiment (APEX) is a radio telescope 5,064 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert in northern Chile, 50 km east of San Pedro de Atacama built and operated by 3 European research institutes. The main dish has a diameter of 12 m and consists of 264 aluminium panels with an average surface accuracy of 17 micrometres (rms). The telescope was officially inaugurated on September 25, 2005.

<span class="mw-page-title-main">Llano de Chajnantor Observatory</span> Observatory

Llano de Chajnantor Observatory is the name for a group of astronomical observatories located at an altitude of over 4,800 m (15,700 ft) in the Atacama Desert of northern Chile. The site is in the Antofagasta Region approximately 50 kilometres (31 mi) east of the town of San Pedro de Atacama. The exceptionally arid climate of the area is inhospitable to humans, but creates an excellent location for millimeter, submillimeter, and mid-infrared astronomy. This is because water vapour absorbs and attenuates submillimetre radiation. Llano de Chajnantor is home to the largest and most expensive astronomical telescope project in the world, the Atacama Large Millimeter Array (ALMA). Llano de Chajnantor and the surrounding area has been designated as the Chajnantor Science Reserve by the government of Chile.

<span class="mw-page-title-main">Associated Universities, Inc.</span> American nonprofit organization

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<span class="mw-page-title-main">Reber Radio Telescope</span> United States historic place

The Reber Radio Telescope is a historic radio telescope, located at the Green Bank Observatory near Green Bank, West Virginia. Built in 1937 in Illinois by astronomer Grote Reber, it is the first purpose-built parabolic radio telescope. It was designated a National Historic Landmark in 1989.

<span class="mw-page-title-main">Green Bank Interferometer</span>

The Green Bank Interferometer (GBI) is a former radio astronomy telescope located at Green Bank, West Virginia (USA) and operated by the National Radio Astronomy Observatory (NRAO). It included three on-site radio telescopes of 85-foot (26m) diameter, designated 85-1, 85-3, and 85-2 and a portable telescope.

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<span class="mw-page-title-main">Violette Impellizzeri</span> Astronomer from Italy

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  2. "Maps & Directions". Retrieved 20 May 2019.
  3. "NRAO Structural Changes: Announcing the Separation of the Green Bank Observatory and the Long Baseline Observatory". Associated Universities, Inc. Retrieved May 20, 2019.
  4. "Other Telescopes at Green Bank". Retrieved May 20, 2019.
  5. "National Radio Quiet Zone — Science Website". Retrieved May 20, 2019.
  6. "NRAO Green Bank Site RFI Regulations for Visitors" (PDF). Retrieved May 20, 2019.
  7. "300-ft telescope at Green Bank Site". Retrieved August 17, 2022.
  8. "NRAO: Socorro, New Mexico". Retrieved 20 May 2019.
  9. "National Radio Astronomy Observatory - Legacy Content - Tucson". Retrieved 20 May 2019.
  10. "Arizona Radio Observatory". Retrieved 20 May 2019.
  11. "ALMA". Retrieved 20 May 2019.
  12. "ALMA Location". Retrieved 20 May 2019.
  13. "Halfway There: 33 ALMA Antennas on Chajnantor". ESO Announcement. Retrieved 15 May 2012.
  14. "Jansky Lecture Redirect". Retrieved 20 May 2019.
  15. "2012 Jansky Lecturer". Retrieved 20 May 2019.