Astronomy and Astrophysics for the 1980's, Volume 1 Report of the Astronomy Survey Committee (1982) / Chapter Skim
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7 PROGRAMS FOR STUDY AND DEVELOPMENT
7 PROGRAMS FOR STUDY AND DEVELOPMENT
Pages 157-166
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From page 157... ...
Long-duration spaceflights of infrared telescopes cooled to cryogenic temperatures; D A very large telescope in space for ultraviolet, optical, and nearinfrared observations; 157
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From page 158... ...
A FUTURE X-RAY OBSERVATORIES IN SPACE The Astronomy Survey Committee recommends the study and development of space observatories beyond the Advanced X-Ray Astrophysics Facility (AXAF)
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From page 159... ...
The first four of these scientific goals (an all-sky survey, measurement of variability, low- to moderate-resolution spectroscopy, and study of low-surface-brightness features, all directed at faint sources) require collecting areas much larger than that of AXAF but angular resolutions sufficient only to avoid source confusion and to permit unambiguous identification of optical and radio counterparts.
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From page 160... ...
Coordinated observations of a wide variety of nearby stars at x-ray, EUV, UV, and optical wavelengths will furnish decisive tests of stellar-atmosphere models and theories of coronal activity. Measurement of the structure and physical conditions in the hot component of the interstellar medium by means of soft x-ray and EUV surveys and
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From page 161... ...
C LONG-DURATION SPACEFLIGHTS OF INFRARED TELESCOPES COOLED TO CRYOGENIC TEMPERATURES The Astronomy Survey Committee recommends the study and development of long-duration space observatories incorporating infrared telescopes cooled to cryogenic temperatures.
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From page 162... ...
However, the scientific return from SIRTF will almost certainly provide an overwhelming case for long-duration spaceflights of cryogenically cooled infrared telescopes. A possible way to achieve this capability is to develop SIRTF itself as a facility for eventual placement onto a space platform, to be refurbished at intervals of 6 to 12 months.
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From page 163... ...
At visual wavelengths it would have a resolving power of about 4 rnilliarcseconds, a limiting magrutude for medium-resolution spectroscopy of about 30, and a limiting magnitude for imaging of about 3Wmore than a hundred times fainter than the faintest object accessible to Space Telescope. A telescope of such power could, for example, observe the planets with resolutions ranging from 12 km at Jupiter to 90 km at Neptune, permitting long-term studies of the atmospheric dynamics of the major planets; observe the star-forming regions in the Orion nebula with a resolution of 10 astronomical units at near-infrared wavelengths, permitting direct observation of the process of star formation and detailed studies of preplanetary nebulae; observe the main sequence in the Andromeda Galaxy tour magnitudes Below tne oldest turn-off point and obtain spectra one magnitude below this point; perform spectroscopy of solar-type stars in nearby galaxies, permitting direct chemicalabundance and abundance-history determinations for these galaxies; with suitable care and stability, obtain relative positions of , .
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From page 164... ...
Further improvements of infrared interferometric capabilities and significant developments in optical interferometry will probably require interferometers in space to escape the deleterious effects of the Earth's atmosphere. A desirable goal is a program of space optical and infrared interferometry leading, by the early part of the next century, to an interferometer with baselines of a few tens of kilometers and resolutions of 1 to 10 microarcseconds at optical wavelengths.
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From page 165... ...
A high-resolution nuclear gamma-ray spectrometer should be included in the mission for the study of the gamma-ray lines from radioactivity in supernova remnants, positron annihilation in the Galactic disk and in extragalactic sources, nuclear excitations caused by cosmic rays in dense matter, and nucleosynthesis in extragalactic supernovae; energy resolution sufficient to study line profiles will be desirable. Development of such instruments, possibly for deployment upon a space platform, should begin as soon as there emerges a clear understanding of the observational requirements from analysis of results from GRO.
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From page 166... ...
In addition, the Committee urges NASA to set aside resources for the establishment of lunar astronomical observatories as an important corollary to the establishment of large-scale industrial or power-generation facilities in Earth orbit. The Moon offers certain decisive advantages as a base for astronomical observations.
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