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.
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.
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.
The Karl G. Jansky Very Large Array (VLA) is a centimeter-wavelength radio astronomy observatory in the southwestern United States. It lies in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, approximately 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.
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.
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.
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).
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.
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 restricted by law to facilitate scientific research and the gathering of military intelligence. About half of the zone is located in the Blue Ridge Mountains of west-central Virginia while the other half is in the Allegheny Mountains of east-central West Virginia; a small part of the zone is in the southernmost tip of the Maryland panhandle.
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.
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.
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.
Associated Universities, Inc. (AUI) is a research management corporation that builds and operates facilities for the research community. It is a not-for-profit 501(c)(3) corporation headquartered in Washington, D.C., United States. The current president is Adam Cohen. The corporation's major current operating unit is the National Radio Astronomy Observatory, which it operates under a Cooperative Agreement with the National Science Foundation.
The Reber Radio Telescope is a historic radio telescope, located at the Green Bank Observatory near Green Bank, West Virginia, USA. Built in 1937 in Illinois by the astronomer Grote Reber, it was the first purpose-built parabolic radio telescope. It was designated a National Historic Landmark in 1989.
The Green Bank Interferometer (GBI) is a former radio astronomy telescope located at Green Bank, West Virginia (US) 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.
The Array Operations Center (AOC) in Socorro, New Mexico, is the control and monitor center for the Very Long Baseline Array. From the AOC, National Radio Astronomy Observatory operators are able to remotely control and monitor the ten VLBA telescope stations over the internet. The operators aim the antennas, select radio frequencies for observation, control the hard drives, and monitor the weather and 'health' of the equipment at every site. A real-time display of the array's status is available for observers to also monitor their observations.
Splatalogue is a database for astronomical spectroscopy which contains information on nearly six million spectral lines and is maintained by the National Radio Astronomy Observatory (NRAO). The name is a portmanteau of "spectral line catalogue".
Jacqueline Henrie͏̈tte van Gorkom is a Dutch radio astronomer and Rutherfurd Professor of Astronomy at Columbia University. Van Gorkom is known for her contributions to the field of galaxy evolution, particularly through observations of neutral hydrogen gas.
David Sutphin Heeschen 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.
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