Extragalactic Radio Sources

OCT 01, 1973

New data from radio telescope arrays are inspiring debate about the physics of galaxies and quasars, the nature of the red shift and perhaps fundamental physics itself.

DOI: 10.1063/1.3128278

Kenneth I. Kellerman

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 ranging from a few days to a few years. The velocities of the component parts of some of the sources have been measured, and they apparently exceed the velocity of light—only one of the many problems that the new data present to astrophysicists.

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More about the Authors

Kenneth I. Kellerman. National Radio Astronomy Observatory, Green Bank, West Virginia.