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Physics Today, 1973
Radio astronomers have recently begun to harvest a wealth of data using instruments with greatly improved sensitivity and resolution. They are now mapping the internal structure of galaxies and quasars over a wide range of the radio spectrum. Variations in the structure as well as in the intensity of these sources are being observed on time scales ...
K.I. Kellermann, I.I.K. Pauliny-Toth
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Radio astronomers have recently begun to harvest a wealth of data using instruments with greatly improved sensitivity and resolution. They are now mapping the internal structure of galaxies and quasars over a wide range of the radio spectrum. Variations in the structure as well as in the intensity of these sources are being observed on time scales ...
K.I. Kellermann, I.I.K. Pauliny-Toth
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Physics Bulletin, 1968
Seldom have astronomers been presented with such an intriguing problem as that of the pulsed radio sources, revealed just over six months ago during a survey made at Cambridge using a new radiotelescope of high sensitivity. The difficulty is to find a satisfactory theory to account for celestial bodies of planetary size which emit flashes of radio ...
F. Hoyle, J. Narlikar
+4 more sources
Seldom have astronomers been presented with such an intriguing problem as that of the pulsed radio sources, revealed just over six months ago during a survey made at Cambridge using a new radiotelescope of high sensitivity. The difficulty is to find a satisfactory theory to account for celestial bodies of planetary size which emit flashes of radio ...
F. Hoyle, J. Narlikar
+4 more sources
1995
Twelve years after the publication of the first results obtained by Jansky in 1932, which marked the beginning of radio astronomy, Reber observed a radio-emission maximum in the constellation Cygnus. It was the first detection of Cygnus A, one of the brightest of all extragalactic sources (that is, located outside our Galaxy) in the radio region. These
Françoise Combes +3 more
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Twelve years after the publication of the first results obtained by Jansky in 1932, which marked the beginning of radio astronomy, Reber observed a radio-emission maximum in the constellation Cygnus. It was the first detection of Cygnus A, one of the brightest of all extragalactic sources (that is, located outside our Galaxy) in the radio region. These
Françoise Combes +3 more
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Advances in Space Research, 1981
Abstract Some recent observational results on extended and compact extragalactic radio sources are described. Theoretical interpretations are critically examined.
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Abstract Some recent observational results on extended and compact extragalactic radio sources are described. Theoretical interpretations are critically examined.
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New Astronomy Reviews, 2002
Abstract This paper describes several modifications to the simplest model of a beam that might have the effect of suppressing the short-wavelength Kelvin–Helmholtz instabilities that can cause jet disruption while maintaining the long-wavelength modes that are popular as causes of distorted jet structure.
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Abstract This paper describes several modifications to the simplest model of a beam that might have the effect of suppressing the short-wavelength Kelvin–Helmholtz instabilities that can cause jet disruption while maintaining the long-wavelength modes that are popular as causes of distorted jet structure.
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Astrometry of Southern radio sources
Astrophysics and Space Science, 1991An overview is presented of a number of astrometry and astrophysics programs based on radio sources from the Parkes 2.7 GHz catalogues. The programs cover the optical identification and spectroscopy of flat-spectrum Parkes sources and the determination of their milliarc-second radio structures and positions.
G L, White +9 more
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Models for Extragalactic Radio Sources
Symposium - International Astronomical Union, 1986Doubt is cast on the reality of the following four assumptions commonly made in the treatment of extragalactic radio sources: (1) The central engine is a black hole; (2) Electrons can be accelerated in situ in the knots and heads of the jets, to large Lorentz factors γ ≥ 102, with an efficiency exceeding 30%; (3) The (non-thermal) radiation emitted by ...
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Alignment of distant radio sources
Nature, 1984A typical extragalactic radio source is a simple double or elongated structure with a well-defined orientation on the sky. In 1972, Willson1 investigated the relative orientation of 74 extragalactic 3C radio sources mapped at the Cambridge 1-mile telescope, and noted that extended extragalactic radio sources tend to be parallel if they are separated by
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Compact steep-spectrum and peaked-spectrum radio sources
Astronomy and Astrophysics Review, 2021D J Saikia
exaly