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36-700: The VLA stands at an elevation of 6,970 feet (2,120 m) above sea level. It is a component of the National Radio Astronomy Observatory (NRAO). The NRAO is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc . The radio telescope comprises 27 independent antennas in use at a given time plus one spare, each of which has a dish diameter of 25 meters (82 feet) and weighs 209 metric tons (230 short tons ). The antennas are distributed along

72-864: A campaign in Congress to replace it with the Green Bank Telescope , construction for which began in 1990. 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

108-517: A decade-long upgrade project resulted in the VLA expanding its technical capacities by factors of up to 8,000. The 1970s-era electronics were replaced with state-of-the-art equipment. To reflect this increased capacity, VLA officials asked for input from both the scientific community and the public in coming up with a new name for the array, and in January 2012 it was announced that the array would be renamed

144-427: A leading role in commissioning the university's 24-foot and 60-foot radio telescopes. After spending one year as an instructor at Wesleyan University he returned to Harvard as a lecturer and research associate. In 1956, NSF awarded a contract to fund a new national facility in radio astronomy to Associated Universities, Inc. (AUI), a consortium of originally nine universities, including Harvard. AUI already held

180-443: 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 pm, 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

216-715: 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. The NRAO headquarters is located on the campus of the University of Virginia in Charlottesville, Virginia . The North American ALMA Science Center and

252-649: 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." 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. The lecture is delivered in Charlottesville , Green Bank , and in Socorro . David S. Heeschen David Sutphin Heeschen (March 12, 1926 – April 13, 2012)

288-627: Is not staffed continuously. Visitors unfamiliar with the area are warned that there is little food on site, or in the sparsely populated surroundings; those unfamiliar with the high desert are warned that the weather is quite variable, and can remain cold into April. For those who cannot travel to the site, the NRAO created a virtual tour of the VLA called the VLA Explorer . The VLA site was previously closed to visitors from March 2020 through October 2022. National Radio Astronomy Observatory The National Radio Astronomy Observatory ( NRAO )

324-489: 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

360-653: The NRAO VLA Sky Survey and Faint Images of the Radio Sky at Twenty-Centimeters . In September 2017 the VLA Sky Survey (VLASS) began. This survey will cover the entire sky visible to the VLA (80% of the Earth's sky) in three full scans. Astronomers expect to find about 10 million new objects with the survey — four times more than what is presently known. The driving force for the development of

396-438: The National Radio Astronomy Observatory announced that they will be replacing the ageing antennae with 160 new ones at the site, plus 100 auxiliary antennae located across North America. The project, estimated to cost about $ 2 billion to build and around $ 90 million to run, will vastly expand the capabilities of the current installation and increase the frequency sensitivity from 50 GHz to over 100 GHz. The facility will be renamed

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432-731: 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. 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. The Arizona Radio Observatory now operates

468-678: The hydrogen gas that constitutes a large portion of the Milky Way galaxy as well as external galaxies. In 1989 the VLA was used to receive radio communications from the Voyager 2 spacecraft as it flew by Neptune . A search of the galaxies M31 and M32 was conducted in December 2014 through January 2015 with the intent of quickly searching trillions of systems for extremely powerful signals from advanced civilizations. It has been used to carry out several large surveys of radio sources, including

504-508: The " Karl G. Jansky Very Large Array". On March 31, 2012, the VLA was officially renamed in a ceremony inside the Antenna Assembly Building. The VLA is a multi-purpose instrument designed to allow investigations of many astronomical objects, including radio galaxies , quasars , pulsars , supernova remnants, gamma-ray bursts , radio-emitting stars , the sun and planets , astrophysical masers , black holes , and

540-406: The " Next Generation Very Large Array ". The VLA is located between the towns of Magdalena and Datil , about 50 miles (80 km) west of Socorro, New Mexico . U.S. Route 60 passes east–west through the complex. The VLA site is open to visitors with paid admission. A visitor center houses a small museum, theater, and a gift shop. A self-guided walking tour is available, as the visitor center

576-504: The 12-Meter Telescope. The Atacama Large Millimeter Array (ALMA) site in Chile is at ~5,000 m (16,000 ft) altitude near Cerro Chajnantor in northern Chile. 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 . The Karl G. Jansky Lectureship

612-808: The 1970, 1980, and 1990 decadal reviews of astronomy and astrophysics . Among other honors, he was president of the American Astronomical Society (1980-1982), a fellow in the American Academy of Arts and Sciences , a member of the American Philosophical Society , and a recipient of the NSF Distinguished Public Service award. An enthusiastic pursuer of serial hobbies, he was at various times an ice skater, hiker, hunter, sports car enthusiast, yachtsman, and ham radio operator,

648-686: The NRAO Technology Center and Central Development Laboratory are also in Charlottesville. 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 . 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

684-477: The VLA is located on the campus of the New Mexico Institute of Mining and Technology in Socorro, New Mexico . The DSOC also serves as the control center for the Very Long Baseline Array (VLBA), a VLBI array of ten 25-meter dishes located from Hawaii in the west to the U.S. Virgin Islands in the east that constitutes the world's largest dedicated, full-time astronomical instrument. In 2011,

720-586: The VLA was David S. Heeschen . He is noted as having "sustained and guided the development of the best radio astronomy observatory in the world for sixteen years." Congressional approval for the VLA project was given in August 1972, and construction began some six months later. The first antenna was put into place in September 1975 and the complex was formally inaugurated in 1980, after a total investment of US$ 78,500,000 (equivalent to $ 290,000,000 in 2023). It

756-425: The antennas are moved every three to four months. Moves to smaller configurations are done in two stages, first shortening the east and west arms and later shortening the north arm. This allows for a short period of improved imaging of extremely northerly or southerly sources. The frequency coverage is 74 MHz to 50 GHz (400 cm to 0.7 cm). The Pete V. Domenici Science Operations Center (DSOC) for

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792-466: 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,

828-575: 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

864-447: The array acts as a single antenna with a variable diameter. The angular resolution that can be reached is between 0.2 and 0.04 arcseconds . There are four commonly used configurations, designated A (the largest) through D (the tightest, when all the dishes are within 600 metres (2,000 ft) of the center point). The observatory normally cycles through all the various possible configurations (including several hybrids) every 16 months;

900-566: The astronomers in Green Bank. All vehicles on the premises are powered by diesel motors to minimize interference by ignition systems. Until its collapse on November 15, 1988, a 300 ft radio telescope 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 am on September 21, 1962. The telescope's first observation

936-435: The contract to manage Brookhaven National Laboratories , but this was quite a different venture. Heeschen resigned his position at Harvard and soon moved with his family to Green Bank, West Virginia , the remote location of the new radio observatory. As the first NRAO scientific staff member, he soon became the assistant to Otto Struve , who had been appointed NRAO director after a rocky search. Indeed, Struve proved unequal to

972-589: The flight (N60NA) experienced an uncontained engine failure , causing cabin decompression . In 1997 the VLA featured in Contact , the film adaptation of the book by the same name written by Carl Sagan . With a view to upgrading the venerable 1970s technology with which the VLA was built, the VLA has evolved into the Expanded Very Large Array (EVLA). The upgrade has enhanced the instrument's sensitivity, frequency range, and resolution with

1008-517: The hardships of the Great Depression . He served one year in the Army at the end of World War II, then enrolled at the University of Illinois intending to study agricultural science. Instead, he received his B.S. degree in engineering physics in 1949, and an M.S. degree in astronomy in 1951. Studying under Bart Bok at Harvard, Heeschen completed his Ph.D. in 1954. At Harvard, Heeschen played

1044-504: The installation of new hardware at the San Agustin site. A second phase of this upgrade may add up to eight additional antennae in other parts of the state of New Mexico , up to 190 miles (300 km) away, if funded. Magdalena Ridge Observatory is a new observatory a few miles south of the VLA, and is run by VLA collaborator New Mexico Tech . Under construction at this site is a ten-element optical interferometer . In June 2023,

1080-448: The task of constructing the planned new 140-foot radio telescope. He resigned, and Heeschen was appointed as acting director at the age of 36, becoming, in 1962, director. During his subsequent eighteen-year tenure, he oversaw the construction of the 140-foot antenna, a 300-foot telescope, a 4-element interferometer; at Tucson, Arizona , a high-precision 36-foot telescope; and the Very Large Array west of Socorro, New Mexico . Heeschen

1116-486: The three arms of a track, shaped in a wye (or Y) -configuration, (each of which measures 21 kilometres (13 mi) long). Using the rail tracks that follow each of these arms—and that, at one point, intersect with U.S. Route 60 at a level crossing—and a specially designed lifting locomotive ("Hein's Trein"), the antennas can be physically relocated to a number of prepared positions, allowing aperture synthesis interferometry with up to 351 independent baselines: in essence,

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1152-775: The universe. 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 km ) 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

1188-493: Was an American radio astronomer , best known for his long and influential tenure as director of the U.S. National Radio Astronomy Observatory (NRAO) during the time that radio astronomy was transformed from a hands-on approach by a few individuals building their own instruments to a discipline with staff-supported user facilities servicing often large teams of dedicated observers. Heeschen grew up in Chicago, Illinois , during

1224-466: Was elected to the National Academy of Sciences in 1971. He resigned as director in 1978, becoming again a member of the NRAO scientific staff. He contributed to the innovative design of the 100-meter Green Bank Telescope which, beginning operation in 2000, became the leading instrument of its kind in the world. His own research was on extragalactic radio sources . He played an active role in

1260-427: 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 ft in height, weighed 600 tons, had a 2-minute arc accuracy, and had

1296-470: Was the largest configuration of radio telescopes in the world. During construction in 1975, workers laying the tracks for the northern arm of the array discovered a human skeleton north of US-60 . A year later, the remains were identified as belonging to a male airline passenger who was ejected from National Airlines Flight 27 at 39,000 feet (12,000 m) two years earlier, after the DC-10-10 servicing

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