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The paper outlines the evolution of the Pioneer Venus program from the initial meeting of a consortium of scientists to study the feasibility of a simple entry probe to Venus, through the Planetary Explorer missions, to the Orbiter Mission proposals. Major recommendations of the 1970 National Academy of Sciences study on Venus exploration planning and of the 1972 Pioneer Venus Science Steering Group report are mentioned.
The Public Service Satellite Consortium evaluated prospects for satellite telecommunications in four areas of the public service: the U.S. health care system, elementary and secondary education, American libraries, and that sector of the public service which is concerned with the provision of continuing education to health professionals. Three important conclusions were reached. First, throughout the public service there are three recurring needs: improved access, cost containment, and maintenance of quality. Appropriate application of communication satellite systems could ameliorate each of these concerns. Second, there appears to be an enormous latent demand for data communication services throughout the public service. The potential demand in 1982 to support requirements in hospital administration, library services and other information-retrieval activities, equipment maintenance, and environmental monitoring may be in excess of $300 million a year. Third, administrative applications of data communication networks show particular promise, especially in rural areas.
Solar system processes are considered along with the origin and evolution of the moon, planetary geophysics, lunar basins and crustal layering, lunar magnetism, the lunar surface as a planetary probe, remote observations of lunar and planetary surfaces, earth-based measurements, integrated studies, physical properties of lunar materials, and asteroids, meteorites, and the early solar system. Attention is also given to studies of mare basalts, the kinetics of basalt crystallization, topical studies of mare basalts, highland rocks, experimental studies of highland rocks, geochemical studies of highland rocks, studies of materials of KREEP composition, a consortium study of lunar breccia 73215, topical studies on highland rocks, Venus, and regional studies of the moon. Studies of surface processes, are reported, taking into account cratering mechanics and fresh crater morphology, crater statistics and surface dating, effects of exposure and gardening, and the chemistry of surfaces.
Color images of the lunar surface from 20 deg W to 120 deg E were prepared which map the variations in the distribution of Al, Mg, and Si as expressed by the ratios of the Al/Si and the Mg/Al fluorescent X-ray intensities. Through the use of image enhancement techniques developed for the La Jolla Consortium on remote sensing of the moon, detailed information previously unobserved has been made available. The frequency distribution of the Apollo 15 and 16 intensity ratios for individual 0.25 x 0.25 deg surface units is clearly bimodal, peaking at 0.81 for mare material and 1.12 for nearside highland material, which values correspond to concentration ratios of 0.39 and 0.54, respectively, for Al/Si.
A computerized array processing system has been developed to reduce, analyze, display, and correlate a large number of orbital and earth-based geochemical, geophysical, and geological measurements of the moon on a global scale. The system supports the activities of a consortium of about 30 lunar scientists involved in data synthesis studies. The system was modeled after standard digital image-processing techniques but differs in that processing is performed with floating point precision rather than integer precision. Because of flexibility in floating-point image processing, a series of techniques that are impossible or cumbersome in conventional integer processing were developed to perform optimum interpolation and smoothing of data. Recently color maps of about 25 lunar geophysical and geochemical variables have been generated.
The paper discusses some of the current and potential markets for satellite data communications as projected by the Public Service Satellite Consortium (PSSC). Organizations in the public service sector are divided into three categories, depending on their expected benefits and organizational changes due to increased satellite telecommunications use: A - modest institutional adjustments are necessary and significant productivity gains are likely; B - institutional requirements picture is promising, but more information is needed to assess benefits and risk; and C - major institutional adjustments are needed, risks are high but possible benefits are high. These criteria are applied to the U.S. health care system, continuing education, equipment maintenance, libraries, environmental monitoring, and other potential markets. The potential revenues are seen to be significant, but what is needed is a cooperative effort by common carriers and major public service institutions to aggregate the market.
Results are summarized for a consortium study of the chemistry, mineralogy, and petrology of seven Luna 24 fragments greater than 1 mm in size and having a mass of about 2 mg each. The fragments include four samples of mare ferrobasalt composition, one vitrophyre with the composition of a Mg-rich VLT mare basalt, one agglutinate, and one plagioclase fragment. It is found that: (1) the ferrobasalt is a highly fractionated mare rock very low in alkalis and TiO2, is similar to the less fractionate Apollo 17 VLT basalts, and is quite low in large-ion lithophile trace-element content; (2) the rare-earth-element patterns of the ferrobasalts are typical of VLT basalt, but some ophitic basalts have positive Eu anomalies, while others have negative Eu anomalies typical of mare basalts; and (3) the agglutinate is feldspathic and similar in composition to soil fines in Fe, Cr, Ca, and Al.
Papers are presented concerning studies of lunar basalts, highland rocks, and meteorites. Specific topics include the petrology and chemistry of basaltic fragments from Apollo 11 soil; the composition, magma types and petrogenesis of Apollo 17 high-Ti mare basalts; the chemistry and probable origin of Apollo 15 green glass; experimental studies of the partitioning of nickel and chromium into olivine from synthetic basaltic melts; the petrology and geochemistry of pristine highland rocks; the argon isotope age systematics of consortium breccia 73255; magnetite-sulfide-metal complexes in the Allende meteorite; the fractionation of refractory lithophile elements in chondritic meteorites; and the origin and relation to enstatite chondrites of aubrites.
Altitudes and relative ages of mare surface units were compared to test if a systematic correlation in height of lava eruption surfaces and age might reflect a corresponding increase in depth of the magma chamber with time; in addition the altitudes were studied to shed light on the time and place of warping of mare surfaces. The laser altimeter data from the Apollo missions and relative age data based on crater erosion models and crater counts were used for the study. The data were correlated by using the image data bank of the Lunar Geoscience Consortium. Results of the first part of the study are inconclusive as no systematic increase in height of lavas with time could be shown. The data of the second part of the study support the conclusion that mare surfaces may have warped throughout most of the time represented by sample ages from the Apollo missions, and that the lithosphere may have become strong enough to remain stable after the time of Apollo 12 samples around 3 b.y. ago.
A Mars average data set (MADS) has been constructed from thermal and albedo measurements of the Viking Infrared Thermal Mapper; by merging information from all longitudes, and ensuring reasonably complete longitudinal sampling, a representation of mean Mars behavior is obtained. Brightness temperatures at 7, 9, 11, 15, and 20 microns and albedo information in the band 0.3-3.0 microns have been binned using 2 deg latitude strips, 24 times of day, 3 emission angle intervals, and 23 nonoverlapping solar longitude periods covering 1.43 Mars years starting at a solar longitude of 84 deg. The MADS is ideally suited to parametric study of latitudinal, diurnal, angular, and seasonal dependences. Data are presented for surface thermal and albedo behavior in clear and dusty atmospheric conditions; the thermal response of the atmospheric temperature to a major dust storm is found to be consistent with Mariner 9 data from the 1971 storm. Examples of use of the MADS, which is available through the Mars Consortium, indicate how averaged data reveal specific surface and atmospheric phenomena.
One of the payloads that the Shuttle will carry into low-earth orbit is the Spacelab, a laboratory designed by a European consortium which will enable scientist-astronauts to conduct research in a shirt-sleeve environment. The typical flight of seven days will permit numerous experiments to be conducted that take advantage of long-term reduced gravity. A description is presented of plans for the conduction of Spacelab experiments which are related to the study of combustion, taking into account also investigations performed in the preparation of such experiments. Attention is given to an overview study of combustion experiments in a space laboratory, droplet burning, flammability limits in a standard tube, the combustion of particle clouds, smoldering combustion in porous fuels, liquid pool burning, and combustion experimentation aboard the space transportation system.
A catalog of lunar and radar anomalies was generated to provide a base for comparison with Venusian radar signatures. The relationships between lunar radar anomalies and regolith processes were investigated, and a consortium was formed to compare lunar and Venusian radar images of craters. Time was scheduled at the Arecibo Observatory to use the 430 MHz radar to obtain high resolution radar maps of six areas of the lunar suface. Data from 1978 observations of Mare Serenitas and Plato are being analyzed on a PDP 11/70 computer to construct the computer program library necessary for the eventual reduction of the May 1981 and subsequent data acquisitions. Papers accepted for publication are presented.
This paper describes the Pacific Basin Communications Study, an assessment of Pacific islands telecommunications requirements, recently completed by the Public Service Satellite Consortium under contract with the National Aeronautics and Space Administration (NASA). The study describes extant and planned telecommunications systems in the region, examines user needs in terms of the development of governmental, social and commercial activities, and proposes and describes alternative technological solutions to communications problems. Questions of financing, implementation, management, costs and benefits of a regional telecommunications system are discussed. This paper describes user requirements based on six months of field investigation and technological options for improving telecommunications in the Pacific islands.
Observations of cool stars with the Einstein Observatory (HEAO-2) have brought about a fundamental change in our knowledge and understanding of stellar coronae. The existence of X-ray emission from stars throughout the H-R diagram, the wide range of X-ray luminosity within a given spectral and luminosity class, and the strong correlation of X-ray luminosity with stellar age and rotation are among the more significant Einstein results. These results are strong evidence for the influence of stellar dynamo action on the formation and heating of stellar coronae. A discussion of relevant consortium and guest observations is given. The Hyades cluster, in particular, serves as an example to demonstrate the usefulness of X-ray observations in the study of stellar activity and coronal evolution.
An air traffic control radar calibration satellite is described that will be used by the U.S. Federal Aviation Administration, U.S. military agencies and cooperating governments around the world to measure antenna patterns associated with the existing international air traffic control network. The satellite will employ three L-band receivers, a UHF command receiver, a VHF telemetry transmitter, associated antennas, a microprocessor, fixed solar arrays, and a power supply to acquire, store and forward signal strength data from some of the tracking radars. A second satellite is planned for launch in 1986 into a high altitude polar orbit with a lifetime of several years in order to provide a long-lived calibration service to the entire international air traffic control system. The initial satellite and associated ground station are being designed and built by a volunteer consortium of three educational institutions and more than a dozen aerospace companies. Following this initial demonstration of a free-flying Getaway Special satellite, a substantial number of organizations are contemplating commercial uses of the concept. Discussions are being held with NASA concerning the establishing of an appropriate fee for this new class of service.
The global color set compiled by the Mars Consortium was investigated. The problem of application of the martian surface color data to geologic interpretation are atmospheric contributions which increase with latitude, and the high correlation among the three color bands. In southern Amenthes the classified units show areas of possible mixing between cratered tarrain and smooth plains. It is suggested that some geologically meaningful correlation exists between surface units and the transformed color data in the Amenthes region. The knobby terrain protruding through the plains units appears to be remnants of ancient cratered terrain extending northward beneath the more youthful smooth plains.
The projected launch date has been delayed approx. 7 weeks from the planned launch date. The Engineering Model (EM) of the automatic measurement and control system (AMCS) is in the critical phase. The contract change no. 1 to the main contract has been signed. A new version of the welding seam location specifications for the wide field camera (WFC) was proposed by the WFC Consortium. The payload integration plan (PIP) has been signed. Production of the EM/QM prototype and ground station equipment has proceeded according to plan with the exception of some delays. Production of the EM equipment has begun. Preparations for the qualification tests of the EM/QM equipment and the integration of EM equipment has begun. The cause of the delay in the launch date include the combined effects of the postponement of the target date for the EM equipment, along with the fact that only a structural model is available.
Subjects of lunar petrology are discussed, taking into account Apollo 14 aluminous mare basalts and their possible relationship to KREEP, the petrology and geochemistry of clasts from consortium breccia, the depths of the mare basalt source region, the origin of olivine at Copernicus, a transient heating event in the history of a highlands troctolite from Apollo 12 soil, and the composition and evolution of the lunar crust in the Descartes highlands. Other topics explored are related to early earth and magmatic processes, differentiated meteorites, chondritic meteorites, other planets and remote sensing, and cratering. Attention is given to the gravity field of Venus at constant altitude and comparison with earth, a spectral analog of Martian soil, dark halo craters and the thickness of grooved terrain on Ganymede, the geomorphology of Rhea, a Monte Carlo model of lunar megaregolith development, the scaling of complex craters, crustal radiogenic heat production and the selective survival of ancient continental crust, and the formation of an impact-generated H2O atmosphere and its implications for the early thermal history of the earth.