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The NRAO VLA Sky Survey (NVSS) was an astronomical survey of the Northern Hemisphere carried out by the Very Large Array (VLA) of the National Radio Astronomy Observatory (NRAO), resulting in an astronomical catalogue. It was led by James J. Condon. [1]
The survey covers 82% sky, consisting of everything north of declination -40 degrees. The observations were made in 'D' and 'DnC' configuration at 1.4 gigahertz (21 cm), with an angular resolution of 45 arcsec. [1] It was proposed at the same time as the Faint Images of the Radio Sky at Twenty-Centimeters, and test observations for both surveys were taken in 1992. [2] Observations were made between September 1993 and October 1996. [1]
The Southern Hemisphere was covered by a similar catalogue called the Sydney University Molonglo Sky Survey (SUMSS), generated using the Molonglo Observatory Synthesis Telescope.[ citation needed ]
A star catalogue or star catalog is an astronomical catalogue that lists stars. In astronomy, many stars are referred to simply by catalogue numbers. There are a great many different star catalogues which have been produced for different purposes over the years, and this article covers only some of the more frequently quoted ones. Star catalogues were compiled by many different ancient people, including the Babylonians, Greeks, Chinese, Persians, and Arabs. They were sometimes accompanied by a star chart for illustration. Most modern catalogues are available in electronic format and can be freely downloaded from space agencies' data centres. The largest is being compiled from the spacecraft Gaia and thus far has over a billion stars.
The European Organisation for Astronomical Research in the Southern Hemisphere, commonly referred to as the European Southern Observatory (ESO), is an intergovernmental research organisation made up of 16 member states for ground-based astronomy. Created in 1962, ESO has provided astronomers with state-of-the-art research facilities and access to the southern sky. The organisation employs about 730 staff members and receives annual member state contributions of approximately €162 million. Its observatories are located in northern Chile.
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.
Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky. This permitted the first high-precision measurements of the intrinsic brightnesses, proper motions, and parallaxes of stars, enabling better calculations of their distance and tangential velocity. When combined with radial velocity measurements from spectroscopy, astrophysicists were able to finally measure all six quantities needed to determine the motion of stars. The resulting Hipparcos Catalogue, a high-precision catalogue of more than 118,200 stars, was published in 1997. The lower-precision Tycho Catalogue of more than a million stars was published at the same time, while the enhanced Tycho-2 Catalogue of 2.5 million stars was published in 2000. Hipparcos' follow-up mission, Gaia, was launched in 2013.
The Hubble Deep Field (HDF) is an image of a small region in the constellation Ursa Major, constructed from a series of observations by the Hubble Space Telescope. It covers an area about 2.6 arcminutes on a side, about one 24-millionth of the whole sky, which is equivalent in angular size to a tennis ball at a distance of 100 metres. The image was assembled from 342 separate exposures taken with the Space Telescope's Wide Field and Planetary Camera 2 over ten consecutive days between December 18 and 28, 1995.
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.
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.
The Digitized Sky Survey (DSS) is a digitized version of several photographic astronomical surveys of the night sky, produced by the Space Telescope Science Institute between 1983 and 2006.
The Molonglo Observatory Synthesis Telescope (MOST) is a radio telescope operating at 843 MHz. It is operated by the School of Physics of the University of Sydney. The telescope is located in Hoskinstown, near the Molonglo River and Canberra, and was constructed by modification of the east–west arm of the former Molonglo Cross Telescope, a larger version of the Mills Cross Telescope.
An astronomical survey is a general map or image of a region of the sky that lacks a specific observational target. Alternatively, an astronomical survey may comprise a set of images, spectra, or other observations of objects that share a common type or feature. Surveys are often restricted to one band of the electromagnetic spectrum due to instrumental limitations, although multiwavelength surveys can be made by using multiple detectors, each sensitive to a different bandwidth.
Associated Universities, Inc. (AUI) is a research management corporation that builds and operates facilities for the research community. AUI is a not-for-profit 501(c)(3) corporation, headquartered in Washington, DC. The President is Dr. Adam Cohen. AUI's major current operating unit is the National Radio Astronomy Observatory (NRAO), which it operates under a Cooperative Agreement with the National Science Foundation.
Gart Westerhout was a Dutch-American astronomer. Well before completing his university studies at Leiden, he had already become well-established internationally as a radio astronomer in the Netherlands, specializing in studies of radio sources and the Milky Way Galaxy based on observations of radio continuum emissions and 21-cm spectral line radiation that originates in interstellar hydrogen. He emigrated to the United States, became a naturalized citizen, and held a number of important scientific and management positions in academic and government institutions.
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.
The Ohio Sky Survey was an astronomical survey of extragalactic radio sources. Data were taken between 1965 and 1971 using the Big Ear radio telescope at the Ohio State University Radio Observatory (OSURO), also known as the "Big Ear Radio Observatory (BERO)".
The C-Band All Sky Survey (C-BASS) is a radio astronomy project that aims to map the entire sky in the C Band (5 GHz). It has been conducted on two radio telescopes, one operating in the Karoo in South Africa, the other at Owens Valley Radio Observatory in California.
Breakthrough Listen is a project to search for intelligent extraterrestrial communications in the Universe. With $100 million in funding and thousands of hours of dedicated telescope time on state-of-the-art facilities, it is the most comprehensive search for alien communications to date. The project began in January 2016, and is expected to continue for 10 years. It is a component of Yuri Milner's Breakthrough Initiatives program. The science program for Breakthrough Listen is based at Berkeley SETI Research Center, located in the Astronomy Department at the University of California, Berkeley.
Faint Images of the Radio Sky at Twenty-Centimeters, or FIRST, was an astronomical survey of the Northern Hemisphere carried out by the Very Large Array. It was led by Robert H. Becker, Richard L. White, and David J. Helfand, who came up with the idea for the survey after they had completed the VLA Galactic Plane survey in 1990, as well as Michael D. Gregg and Sally A. Laurent-Muehleisen. The survey was started 50 years after the first systematic survey of the radio sky was completed by Grote Reber in April 1943.
The Green Bank Observatory is an astronomical observatory located in the National Radio Quiet Zone in Green Bank, West Virginia, U.S. It is the operator of the Robert C. Byrd Green Bank Telescope, the world's largest fully steerable radio telescope.
Barry Gillespie Clark is an American astronomer who led the development of the world's first digitally recorded, software correlated Very Long Baseline Interferometry (VLBI) system for radio astronomy, the Green Bank Interferometer. He was also heavily involved in the development of the Very Large Array and the Very Long Baseline Array.
The 40-foot radio telescope at Green Bank Observatory in the U.S. state of West Virginia was constructed in 1961, and started observing a selection of variable radio sources in the same year, completing its observations in 1968. It became the first automated telescope in 1962. It was subsequently used during summer schools, and in 1987 it was repurposed as an educational telescope, as well as continuing to observe radio sources. In 2021 the telescope celebrated its sixtieth anniversary, having been in continuous use since its 1987 restoration, and used by more than 1,500 students.