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A radio noise source is a device that emits radio waves at a certain frequency, used to calibrate radio telescopes such that received data may be compared to a known value, as well as to find the focal point of a telescope soon after construction, so that the wave guide and front end may be properly located.
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.
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.
Observational astronomy is a division of astronomy that is concerned with recording data about the observable universe, in contrast with theoretical astronomy, which is mainly concerned with calculating the measurable implications of physical models. It is the practice and study of observing celestial objects with the use of telescopes and other astronomical instruments.
Parkes Observatory is a radio astronomy observatory, located 20 kilometres (12 mi) north of the town of Parkes, New South Wales, Australia. It hosts Murriyang, the 64 m CSIRO Parkes Radio Telescope also known as "The Dish", along with two smaller radio telescopes. The 64 m dish was one of several radio antennae used to receive live television images of the Apollo 11 Moon landing. Its scientific contributions over the decades led the ABC to describe it as "the most successful scientific instrument ever built in Australia" after 50 years of operation.
The Australia Telescope Compact Array (ATCA) is a radio telescope operated by CSIRO at the Paul Wild Observatory, twenty five kilometres (16 mi) west of the town of Narrabri in New South Wales, Australia. Its opening ceremony took place on September 2, 1988.
Onsala Space Observatory (OSO), the Swedish National Facility for Radio Astronomy, provides scientists with equipment to study the Earth and the rest of the Universe. The observatory operates two radio telescopes in Onsala, 45 km south of Gothenburg, and takes part in several international projects. Examples of activities:
Owens Valley Radio Observatory (OVRO) is a radio astronomy observatory located near Big Pine, California (US) in Owens Valley. It lies east of the Sierra Nevada, approximately 350 kilometers (220 mi) north of Los Angeles and 20 kilometers (12 mi) southeast of Bishop. It was established in 1956, and is owned and operated by the California Institute of Technology (Caltech). The Owens Valley Solar Array portion of the observatory has been operated by New Jersey Institute of Technology (NJIT) since 1997.
The Combined Array for Research in Millimeter-wave Astronomy (CARMA) was an astronomical instrument comprising 23 radio telescopes, dedicated in 2006. These telescopes formed an astronomical interferometer where all the signals are combined in a purpose-built computer to produce high-resolution astronomical images. The telescopes ceased operation in April 2015 and were relocated to the Owens Valley Radio Observatory for storage.
The RATAN-600 is a radio telescope in Zelenchukskaya, Karachay–Cherkess Republic, Russia. It comprises a 576 m diameter circle of rectangular radio reflectors and a set of secondary reflectors and receivers, based at an altitude of 970 m. Each of the 895 2×7.4 m reflectors can be angled to reflect incoming radio waves towards a central conical secondary mirror, or to one of five parabolic cylinders. Each secondary reflector is combined with an instrumentation cabin containing various receivers and instruments. The overall effect is that of a partially steerable antenna with a maximum resolving power of a nearly 600 m diameter dish, when using the central conical receiver, making it the world's largest-diameter individual radio telescope.
A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally it was an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects – an optical telescope. Nowadays, the word "telescope" is defined as a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors.
A point source is a single identifiable localised source of something. A point source has negligible extent, distinguishing it from other source geometries. Sources are called point sources because in mathematical modeling, these sources can usually be approximated as a mathematical point to simplify analysis.
Spektr-R was a Russian scientific satellite with a 10 m (33 ft) radio telescope on board. It was launched on 18 July 2011 on a Zenit-3F launcher from Baikonur Cosmodrome, and was designed to perform research on the structure and dynamics of radio sources within and beyond the Milky Way. Together with some of the largest ground-based radio telescopes, the Spektr-R formed interferometric baselines extending up to 350,000 km (220,000 mi).
The Primeval Structure Telescope (PaST), also called 21 Centimetre Array (21CMA), is a Chinese radio telescope array designed to detect the earliest luminous objects in the universe, including the first stars, supernova explosions, and black holes. All of these objects were strong sources of ultraviolet radiation, so they ionised the material surrounding them. The structure of this reionisation reflects the overall density structure at the redshift of luminous-object formation.
The Suffa RT-70 radio telescope is an RT-70 radio telescope at the Suffa Radio Observatory on the Suffa plateau in Uzbekistan.
A pulsar timing array (PTA) is a set of galactic pulsars that is monitored and analysed to search for correlated signatures in the pulse arrival times on Earth. As such, they are galactic-sized detectors. Although there are many applications for pulsar timing arrays, the best known is the use of an array of millisecond pulsars to detect and analyse long-wavelength gravitational wave background. Such a detection would entail a detailed measurement of a gravitational wave (GW) signature, like the GW-induced quadrupolar correlation between arrival times of pulses emitted by different millisecond pulsar pairings that depends only on the pairings' angular separations in the sky. Larger arrays may be better for GW detection because the quadrupolar spatial correlations induced by GWs can be better sampled by many more pulsar pairings. With such a GW detection, millisecond pulsar timing arrays would open a new low-frequency window in gravitational-wave astronomy to peer into potential ancient astrophysical sources and early Universe processes, inaccessible by any other means.
The European Pulsar Timing Array (EPTA) is a European collaboration to combine five 100-m class radio-telescopes to observe an array of pulsars with the specific goal of detecting gravitational waves. It is one of several pulsar timing array projects in operation, and one of the four projects comprising the International Pulsar Timing Array, the others being the Parkes Pulsar Timing Array, the North American Nanohertz Observatory for Gravitational Waves, and the Indian Pulsar Timing Array.
Time-domain astronomy is the study of how astronomical objects change with time. Though the study may be said to begin with Galileo's Letters on Sunspots, the term now refers especially to variable objects beyond the Solar System. Changes over time may be due to movements or changes in the object itself. Common targets included are supernovae, pulsating stars, novas, flare stars, blazars and active galactic nuclei. Visible light time domain studies include OGLE, HAT-South, PanSTARRS, SkyMapper, ASAS, WASP, CRTS, GOTO and in a near future the LSST at the Vera C. Rubin Observatory.
The Lunar Crater Radio Telescope (LCRT) is a proposal by the NASA Institute for Advanced Concepts (NIAC) to create an ultra-long-wavelength radio telescope inside a lunar crater on the far side of the Moon.
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