Results 181 to 190 of about 37,310 (215)

Extragalactic Variable Radio Sources

Nature, 1970
Clues to the origin of the enormously energetic activity in quasars and galactic nuclei may come from observations of the varying radio emission from several objects outside the Galaxy. The varying signals from these objects often seem to come from areas which are only a few light months in diameter.
M. J. REES, M. SIMON
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Extragalactic Radio 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, Patrick Boissé, Alain Mazure, Alain Blanchard   +3 more
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Extragalactic radio sources

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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Models for Extragalactic Radio Sources

Symposium - International Astronomical Union, 1986
Doubt 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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Polarization Properties Of Extragalactic Radio Sources

Annual Review of Astronomy and Astrophysics, 1988
D J Saikia
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Surveys of extragalactic radio sources

EAS Publications Series, 2005
Nearly all discrete radio sources are extragalactic and lie at cosmological distances. Most sources stronger than ~1 mJy at 1.4 GHz are powered by active galactic nuclei (AGNs), while the majority of fainter sources are in starburst galaxies. Recent all-sky surveys have detected most of this AGN population, and smaller surveys are now sensitive enough ...
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Modelling Extended Extragalactic Radio Sources

Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics, 2000
Abstract This paper examines the process of modelling a complex empirical phenomenon in modern astrophysics: extended extragalactic radio sources. I show that modelling is done piecemeal, addressing selected striking or puzzling features of that phenomenon separately and individually.
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Polarization properties of extragalactic radio sources

Astrophysics and Space Science, 1979
In order to give a good description of the polarization properties of extragalactic radio sources together with some other radio and optical data for these sources, all published polarization observations of extragalactic radio sources from 1965 to the middle of 1974 have been collected.
W. Eichendorf, M. Reinhardt
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Jets in extragalactic radio sources

AIP Conference Proceedings, 1979
Particle acceleration in the extended parts of radio galaxies seems likely from a number of arguments. The radio jets which now seem commonly to connect the nucleus to the more extended structure of radio galaxies are a likely location for some of the necessary in situ acceleration.
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Evolution of Extragalactic Radio Sources

EAS Publications Series, 2001
I review the current paradigm for extragalactic radio sources including their classification, relationship to their host galaxies, their environments, their propagation, and their lifetimes. I emphasize recent progress in our understanding of radio source evolution and I discuss the current open questions.
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