Astronomy and Astrophysics for the 1980's, Volume 2 Reports of the Panels (1983) / Chapter Skim
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II. The Nature of High-Energy Astronomy and the Scope of the Report
II. The Nature of High-Energy Astronomy and the Scope of the Report
Pages 2-8
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From page 2... ...
They were noted as ominous "guest stars" in the ancient Chinese court records, recognized as stellar outbursts by Tycho Brahe in the sixteenth century, and understood for the first time in the 1930's to be cataclysmic explosions of stars. Since then, observation and theory have shown that every massive star ultimately reaches a critical condition in its evolution when its core suddenly collapses, releasing an amount of gravitational energy comparable with that which would be obtained by converting about one tenth of a solar mass into energy according to Einstein's formula E = mc2.
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From page 3... ...
A distant quasar, radiating x rays with the power of a trillion suns, may wax or wane by a factor of 2 within a few hours. Rapid changes in such enormous luminosities imply highly concentrated energy sources with temperatures and densities utterly beyond the scope of terrestrial experience.
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From page 4... ...
_ , assimilate the flood of discoveries from the first satellite x-ray observatory, Uhuru, launched in December 1970. Already available were a catalog of over 100 x-ray sources and results that revealed the existence of extremely luminous x-ray pulsators in close binary systems, evidence of a black hole, x-ray emission from active galaxies and one quasar, numerous unidentified but apparently extragalactic sources radiating predominantly in the x-ray region, and x rays from hot intergalactic gas in clusters of galaxies.
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From page 5... ...
While high-energy astronomy in the United States achieved extraordinary advances throughout the 1970's, it now faces the certainty of a virtual standstill during the first half of the 1980's. The paucity of new starts on major space projects in high-energy astronomy during the past several years and the delays and reductions in funding of the few ongoing projects have caused a widening gap in observational capabilities.
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From page 6... ...
During the past decade all areas of high-energy astronomy benefited from rapid growth in observational capabilities based on the developing technologies of x-ray optics, radiation detection, solid state electronics, space instrumentation, and data processing. In six years the sensitivity of resonant-bar gravitationalwave detectors, measured in terms of minimum detectable energy flux, has been improved tenfold, and another thousandfold improvement is imminent.
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From page 7... ...
Supporting research and technology must be considered an essential ongoing activity in each of the subdisciplines, sustained at a level of effort commensurate with the technical opportunities and relatively unaffected by the delays in funding of large projects. Looking forward to the 1990's, we see an urgent need to stimulate and encourage the development of new technologies that will advance high-energy astronomy beyond the status we see it attaining in the 1980's on the bases of current instrumentation concepts.
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From page 8... ...
Among the many important new scientific opportunities that beckon high-energy astronomy in the 1980's, we believe that at present those in x-ray astronomy are the most numerous and exciting. It has become clear in the past decade that x-ray observations provide unique information not only about exotic astrophysical processes connected with collapsed stellar objects and supernova remnants but also about stars of all types, the interstellar medium, normal galaxies, radio galaxies, active galactic nuclei, and clusters of galaxies.
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