Astronomy and Astrophysics for the 1980's, Volume 1 Report of the Astronomy Survey Committee (1982) / Chapter Skim
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6 NEW PROGRAMS
6 NEW PROGRAMS
Pages 133-156
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A New Technology Telescope (N=) of the 15-m class operating from the ground at wavelengths of 0.3 to 20 ~m, with relevant design studies to be undertaken immediately; and 4.
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MAJOR NEW PROGRAMS 1. Advanced X-Ray Astrophysics Facility The Astronomy Survey Committee recommends the construction of an Advanced X-Ray Astrophysics Facility (AXAF)
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~e NAB) Array of Radio Telescopes The Astronomy Survey Committee recommends the construction of a ground-based Very-Long-Baseline (VERB)
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From page 136... ...
Through the method of statistical parallaxes, it will furthermore permit direct measurements of distances to many objects throughout our Galaxy and even to some in nearby galaxies. The VERB Array can also be applied to important problems in Earth science (including precision geodesy and geophysics)
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From page 137... ...
of the 15-Meter Class The Astronomy Survey Committee recommends the construction of a New Technology Telescope (NTT) of the 15-m class on the ground for observations in the optical and in the near- and mid-infrared regions of the spectrum (0.3- to 20-~m wavelength)
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From page 138... ...
NTT will provide a probe of gas dynamics in regions of star formation by permitting the examination of optical and infrared spectral lines at very high spectral resolution on an exceedingly fine spatial scale. Present observations indicate that the brightest protostellar candidates are about 1 arcsec in diameter in the 2-10-~m wavelength region, whereas the diffraction limit of a filled-aperture 15-m telescope is about 0.0~0.15 arcsec over the same range; thus, the use of NTT with interferometric techniques will permit detailed study of the geometry and structure of such objects.
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4. A Large Deployable Reflector in Space The Astronomy Survey Committee recommends the construction of a Large Deployable Reflector (LDR)
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MODERATE NEW PROGRAMS 1. Explorer Program Augmentation The Astronomy Survey Committee recommends an immediate and substantial augmentation to the NASA Explorer satellite program, with the aim of restoring it to at least the healthy real level of effort of 1970.
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The Astronomy Survey Committee believes that such a limitation would present a serious obstacle to the progress of space astronomy during the coming decade. Today's Explorer budget, as currently charged for mission costs, provides only about half the support in real terms that was available to the Explorer program a decade ago.
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From page 142... ...
A primary aim of such an investigation is an accurate determination of the isotopic composition of the elements through nickel in a direct sample of contemporary solar and Galactic interstellar matter. In addition, it should be possible to analyze the composition of solar energetic particles through uranium and to study the processes that accelerate particles on the Sun and in the interstellar medium.
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From page 143... ...
143 Two further possibilities merit detailed study by NASA and by other advisory groups for inclusion in the Explorer program. The first is an Explorer satellite to map the Milky Way at moderate angular resolution, both in the lines of selected submillimeter-wavelength transitions thought to be important for the heating and cooling of interstellar gas clouds and in wavelength bands relevant to determinations of temperature and density distributions in cold clouds.
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From page 144... ...
In the spectral region between the 912-A absorption edge of neutral hydrogen and the 1200-A onset of reflectivity of the ST mirror coatings lie many important features critical to the understanding of the interstellar gas, extended stellar atmospheres, supernova remnants, galactic nuclei, and gaseous halos of planets. Atomic and molecular lines not detectable in the ST spectral region include the resonance lines of O+5, seen in stellar coronas and in interstellar space; Of and N+ resonance lines needed for the determination of nitrogen and oxygen abundances in ionized H ~ regions; and the lines of H I, H2, and HD, which are important for understanding the chemistry of molecular clouds and for determining the cosmic D/H ratio.
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From page 145... ...
145 3. A Space VERB Interferometry Antenna The Astronomy Survey Committee recommends the placement of a space VERB interferometry radio antenna in low-Earth orbit to extend the powerful V~BI technique into space in parallel with the rapid completion of a ground-based VERB Array.
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4. Construction of Opticalllnfrared Telescopes in the 2-5-Meter Class The Astronomy Survey Committee recommends the construction of optical/infrared telescopes in the 2-5-m class during the coming de
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Optical/infrared telescopes in the 2-5-m class have made critically important contributions to most of our recently acquired knowledge in a number of key areas, including the following: · Evidence of galaxy evolution from studies of distant galaxies; · The crucial quasar observations that established the existence of the first known gravitational lens; · A mass estimate for the dense component of an x-ray binary star, establishing it as the leading black-hole candidate; · The discovery of quasars in clusters of galaxies, demonstrating that at least some quasars are at the great cosmological distances implied by their large red shifts; · Dynamical studies of hundreds of galaxies in clusters, showing that the bulk of the matter in the Universe is nonluminous at optical wavelengths and has therefore escaped direct detection; · Observations providing strong evidence that interstellar shock waves play a role in star formation; · Demonstration that the old stars in our Galaxy are anomalously rich in oxygen, supporting the hypothesis that the protogalactic gas was enriched by an early generation of massive, short-lived stars; · Detection of activity cycles in solar-type stars and observations of the modulation of chromospheric features by stellar rotation; · Discovery of a binary-star system (SS 433) emitting huge streams of matter at about one fourth of the speed of light; and · Optical confirmation of the existence of pulsars.
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5. Advanced Solar Observatory in Space The Astronomy Survey Committee recommends the establishment in space of an Advanced Solar Observatory (ASO)
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6. Cosmic-Ray Experiments The Astronomy Survey Committee recommends a series of cosmicray experiments in space, to promote the study of solar and stellar activity, the interstellar medium, the origin of the elements, and violent solar and stellar processes.
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7. Astronomical Search for Extraterrestrial Intelligence The Astronomy Survey Committee recommends an astronomical Search for Extraterrestrial Intelligence (SETI)
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151 C SMALL NEW PROGRAMS A 10-Meter Submillimeter-Wave Antenna The Astronomy Survey Committee recommends the construction of a submillimeter-wave telescope of about 10-m aperture at a high, dry site.
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A Spatial Interferometer for the Mid-Infrared Region The Astronomy Survey Committee recommends the construction during the early 1980's of a dedicated two-element spatial interferometer for the mid-infrared spectral region with design parameters optimized for operation at a wavelength of 10 ~m. The spectacular success of radio interferometry since World War II has illustrated forcefully the benefits of interferometry to astronomy.
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From page 153... ...
A Program of High-Precision Optical Astrometry The Astronomy Survey Committee recommends support for the design and construction of innovative devices that offer the promise of greatly improved astrometric precision, particularly those that may help permit the detection of planets around other stars. Since the 1960's, the typical accuracy of observed stellar parallaxes has improved from +16 milliarcseconds to +3 milliarcseconds; the Committee recommends support for the design and construction of innovative devices that offer the potential for obtaining relative positions with an accuracy of +0.1 milliarcsecond.
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The Astronomy Survey Committee therefore recommends that urgent steps be taken to maintain scientific expertise at U.S. universities by ensuring that excellent younger researchers continue to flow into them during the critical decade ahead.
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The Committee furthermore urges the universities themselves to take the following steps to respond to the declining student enrollments and reduced faculty retirements anticipated during the 1980's: implementing procedures that encourage the early retirement of faculty, the establishment of "parallel track" positions of high prestige, and the permitting of non-tenure-track scientists with appropriate qualifications to serve as Principal Investigators on contracts and grants. Some universities have also experimented with so-called "rolling tenure," by which a scientist is granted tenure for the duration of supporting funding from a contract or grant, with tenure extended in step with funding renewal.
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From page 156... ...
Speckle interferometry permits resolution of a stellar disk. The top frame represents a short-exposure stellar image of ~ Ceti; at the lower right is the speckle image of an unresolved star, ~ Ceti; and at the lower lefties the resolved image of the surface of a red giant star, Mira, or 0 Ceti.
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