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Third Cambridge Catalogue Of Radio Sources
The Third Cambridge Catalogue of Radio Sources (3C) is an astronomical catalogue of celestial radio sources detected originally at 159 MHz, and subsequently at 178 MHz. History 3C The catalogue was published in 1959 by members of the Cavendish Astrophysics Group, Radio Astronomy Group of the University of Cambridge. Entries in the catalogue are identified by the prefix "3C" followed by the entry number, with a space - for example, 3C 273. The number denotes objects in order of increasing right ascension. The catalogue was produced using the Cambridge Interferometer on the west side of Cambridge. The interferometer had previously been used for the Second Cambridge Catalogue of Radio Sources (2C) survey, published in 1955. 3CR The catalogue was subsequently revised by Bennett in 1962 using observations at 178 MHz, and for many years '3CR' was considered as the definitive listing of the brighter radio sources in the Northern Hemisphere. The revision resulted in a num ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Catalogue
An astronomical catalogue is a list or tabulation of astronomical objects, typically grouped together because they share a common type, Galaxy morphological classification, morphology, origin, means of detection, or method of discovery. The oldest and largest are star catalogues. Hundreds have been published, including general ones and special ones for such objects as Infrared astronomy, infrared stars, variable stars, giant stars, multiple star systems, star clusters, and so forth. General catalogues for deep-sky objects or for objects other than stars are also large. Again, there are specialized ones for nebulas, galaxies, X-ray astronomy, X-ray sources, Astronomical radio source, radio sources, quasars and other classes. The same is true for asteroids, comets and other Small Solar System body, solar system bodies. Astronomical catalogues such as those for asteroids may be compiled from multiple sources, but most modern catalogues are the result of a particular astronomical su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Julia Riley
Julia M. Riley (née Hill, born 1947) is a British astrophysicist who developed the Fanaroff–Riley classification. Personal and professional background She is the daughter of Philippa (born Pass) and British marine geophysicist Maurice Hill and granddaughter of Nobel Prize–winning physiologist Archibald Vivian Hill. Riley is a Fellow of Girton College associated with the Cavendish Astrophysics Group at University of Cambridge. Her primary field of research is in the area of radio astronomy. Riley lectures and supervises physics within the Natural Sciences Tripos at the University of Cambridge. Fanaroff–Riley type I and II In 1974, along with Bernard Fanaroff, she wrote a paper classifying radio galaxies into two types based on their morphology (shape). Fanaroff and Riley's classification became known as Fanaroff–Riley type I and II of radio galaxies (FRI and FRII). In FRI sources the major part of the radio emission comes from closer to the centre of the source, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monthly Notices Of The Royal Astronomical Society
''Monthly Notices of the Royal Astronomical Society'' (MNRAS) is a peer-reviewed scientific journal in astronomy, astrophysics and related fields. It publishes original research in two formats: papers (of any length) and letters (limited to five pages). MNRAS publishes more articles per year than any other astronomy journal. The learned society journal has been in continuous existence since 1827 and became online only in 2020. It operates as a partnership between the Royal Astronomical Society (RAS), who select and peer-review the contents, and Oxford University Press (OUP), who publish and market the journal. Despite its name, MNRAS is no longer monthly, nor does it carry the notices of the RAS. In 2024 MNRAS became a purely gold open access journal. History The first issue of MNRAS was published on 9 February 1827 as ''Monthly Notices of the Astronomical Society of London'' and it has been in continuous publication ever since. It took its current name from the second vo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memoirs Of The Royal Astronomical Society
The Royal Astronomical Society (RAS) is a learned society and charity that encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science. Its headquarters are in Burlington House, on Piccadilly in London. The society has over 4,000 members, known as fellows, most of whom are professional researchers or postgraduate students. Around a quarter of Fellows live outside the UK. The society holds monthly scientific meetings in London, and the annual National Astronomy Meeting at varying locations in the British Isles. The RAS publishes the scientific journals ''Monthly Notices of the Royal Astronomical Society'', ''Geophysical Journal International'' and ''RAS Techniques and Instruments'', along with the trade magazine '' Astronomy & Geophysics''. The RAS maintains an astronomy research library, engages in public outreach and advises the UK government on astronomy education. The society recognises achievement in astronomy an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3C 66A
3C 66A is a blazar located in the constellation Andromeda. The "distance" of a far away galaxy depends on the distance measurement used. With a redshift of 0.444, light from this active galaxy is estimated to have taken around 4.5 billion years to reach Earth. But as a result of the expansion of the Universe, the present (co-moving) distance to this galaxy is about 5.4 billion light-years (1647 M pc). Even at this great distance this blazar has an apparent magnitude Apparent magnitude () is a measure of the Irradiance, brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction (astronomy), ... of about 15.5. Although 0.444 is used as the common redshift value, 0.3347 is a new strict lower limit "inferred through observing the far-UV absorption by the low-z IGM." 3C 66A underwent an optical outburst in 2007 August, as monitored by the Tuorla blazar monit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BL Lac Object
A BL Lacertae object or BL Lac object is a type of active galactic nucleus (AGN) or a galaxy with such an AGN, named after its prototype, BL Lacertae. In contrast to other types of active galactic nuclei, BL Lacs are characterized by rapid and large-amplitude flux variability and significant optical polarization. Because of these properties, the prototype of the class (BL Lac) was originally thought to be a variable star. When compared to the more luminous active nuclei (quasars) with strong emission lines, BL Lac objects have spectra dominated by a relatively featureless non-thermal emission continuum over the entire electromagnetic range. This lack of spectral lines historically hindered identification of the nature and distance of such objects. In the unified scheme of radio-loud active galactic nuclei, the observed nuclear phenomenology of BL Lacs is interpreted as being due to the effects of the relativistic jet closely aligned to the line of sight of the observer. BL Lacs a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3C 66B
3C 66B is an elliptical radio galaxy located in the constellation Andromeda. With an estimated redshift of 0.021258, the galaxy is about away. It has an angular separation of from the blazar 3C 66A, but the two are most likely unrelated. 3C 66B is an outlying member of Abell 347, which is part of the Perseus–Pisces Supercluster. Observations This is a giant elliptical galaxy that is classified as a low-luminosity Fanaroff and Riley class 1 radio galaxy. Maps of the radio structure suggested that the emission is being shaped by the motion of the galaxy through an ambient medium. A strong jet and counter-jet extend about from the nucleus. These jets have been observed in radio, infrared, optical, ultraviolet, and X-ray bands. Gamma ray emission has been detected coming from the direction of this galaxy, which were most likely emitted from the core region. Observations with the Hubble Space Telescope in 1990 showed that the jet has a filamentary, double-stranded structure. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Janskys
The jansky (symbol Jy, plural ''janskys'') is a non-SI unit of spectral flux density, or spectral irradiance, used especially in radio astronomy. It is equivalent to 10−26 watts per square metre per hertz. The ''spectral flux density'' or ''monochromatic flux'', , of a source is the integral of the spectral radiance, , over the source solid angle: S = \iint\limits_\text B(\theta,\phi) \,\mathrm\Omega. The unit is named after pioneering US radio astronomer Karl Guthe Jansky and is defined as Since the jansky is obtained by integrating over the whole source solid angle, it is most simply used to describe point sources; for example, the Third Cambridge Catalogue of Radio Sources (3C) reports results in janskys. * For extended sources, the surface brightness is often described with units of janskys per solid angle; for example, far-infrared (FIR) maps from the IRAS satellite are in megajanskys per steradian (MJy⋅sr−1). * Although extended sources at all wavelengths can be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Galaxy
A radio galaxy is a galaxy with giant regions of radio emission extending well beyond its visible structure. These energetic radio lobes are powered by jets from its active galactic nucleus. They have luminosities up to 1039 W at radio wavelengths between 10 MHz and 100 GHz. The radio emission is due to the synchrotron process. The observed structure in radio emission is determined by the interaction between twin jets and the external medium, modified by the effects of relativistic beaming. The host galaxies are almost exclusively large elliptical galaxies. ''Radio-loud'' active galaxies can be detected at large distances, making them valuable tools for observational cosmology. Recently, much work has been done on the effects of these objects on the intergalactic medium, particularly in galaxy groups and clusters. The term "radio galaxy" is often used to refer to the entire jet system, rather than solely to its host galaxy. Some scientists consider the term " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malcolm Longair
Malcolm Sim Longair (born 18 May 1941)Anon (2017) is a British physicist. From 1991 to 2008 he was the Jacksonian Professor of Natural Philosophy in the Cavendish Laboratory at the University of Cambridge. Since 2016 he has been Editor-in-Chief of the ''Biographical Memoirs of Fellows of the Royal Society''. Education He was born on 18 May 1941, and educated at Morgan Academy, Dundee, Scotland. He graduated in Electronic Physics from Queen's College, Dundee, which later became the University of Dundee, but was then part of the University of St Andrews, in 1963. He became a research student in the Radio Astronomy Group of the Cavendish Laboratory, Cambridge, where he completed his PhD in 1967 supervised by Martin Ryle. Career and research From 1968 to 1969, he was a Royal Society Exchange Visitor to the Lebedev Institute of the USSR Academy of Sciences, where he worked with Vitaly Ginzburg and Yakov Zeldovich. He held a Fellowship of the Royal Commission for the Exhibiti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3C 324
3C may refer to: In astronomy: * 3C, the ''Third Cambridge Catalogue of Radio Sources'', an astronomical reference series In business: * 3C Records * 3C (radio), a defunct digital radio station * 3C (trade association), an American trade association. * Three-cent piece * Long March 3C, a 2008 Chinese orbital rocket * Team 3C Casalinghi Jet Androni Giocattoli, a defunct Italian professional cycling team * 3C, the former IATA code for defunct American airline RegionsAir * The IATA code for Air Chathams In computing: * Three Cs (Compulsory, Capacity, and Conflict), three categories of CPU cache misses * An abbreviation often used in Taiwan for "computer, communication, and consumer electronics" * Computer Control Company, Inc., a pioneering minicomputer company (1953–1966) * Agile model: 3C (Card, Conversation, Confirmation) In genetics: * Alpha-tubulin 3C, a human gene * 3C, or Chromosome conformation capture, a technique used in molecular biology Substituted amphetamine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavendish Astrophysics Group
The Cavendish Astrophysics Group (formerly the Radio Astronomy Group) is based at the Cavendish Laboratory at the University of Cambridge. The group operates all of the telescopes at the Mullard Radio Astronomy Observatory except for the 32m MERLIN telescope, which is operated by Jodrell Bank. The group is the second largest of three astronomy departments in the University of Cambridge. Instruments under development by the group * The Atacama Large Millimeter Array (ALMA) - several modules of this international project * The Magdalena Ridge Observatory Interferometer (MRO Interferometer) * The SKA * The Radio Experiment for the Analysis of Cosmic Hydrogen (REACH) Instruments in service * The Arcminute Microkelvin Imager (AMI) * A Heterodyne Array Receiver for B-band (HARP-B) at the James Clerk Maxwell Telescope * The Planck Surveyor Previous instruments * The CLOVER telescope * The Very Small Array * The 5 km Ryle Telescope * The Cambridge Optical Aperture Sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
