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The U.S. Space Policy concerning the investment and direct participation in the establishment and operations of remote sensing systems is addressed. Private sector views and state and local government views are presented. Results of a market analysis are pregiven and the economic feasibility of such a program is considered.
The large-scale morphology and internal structure of sector boundaries (SB) are investigated, using observations at 1 AU of interplanetary SB crossings. It was found that the durations of the SBs were either relatively short (less than about 10 min) or relatively long (longer than about 3 hours). Using the minimum variance technique, it was found that the SB surfaces were inclined appreciably with respect to the ecliptic at this epoch of the solar cycle (1971-1973). Magnetic holes were found in thick SBs at a rate about three times that elsewhere. In addition, an analysis of tangential discontinuities showed that their orientations were generally not related to the orientations of the SB surface, but their characteristics were very similar to those for discontinuities outside the SBs.
The results achieved during the first eight months of a program to transfer LANDSAT technology to practicing professionals in the private and public sectors (grass roots) through community colleges and other locally available institutions are reported. The approach offers hands-on interactive analysis training and demonstrations through the use of color desktop computer terminals communicating with a host computer by telephone lines. The features of the terminals and associated training materials are reviewed together with plans for their use in training and demonstration projects.
The variation of the geomagnetic activity index Ap at the IMF sector boundaries (+ to - and - to +) has been studied for three solar cycles, separating data into vernal and autumnal equinoxes. It was found that a reported increase in Ap as an effect of a Hale boundary can be better attributed to the occurrence of a negative IMF Bz component in the geocentric solar magnetospheric coordinate system and to the occurrence of high speed solar wind streams.
The involvement of the Federal government in civilian sector research and development is discussed. Relevant policies are put in an historical perspective. The roles played by industrial research and public funding are reveiwed. Government support of basic an generic research, clientele-oriented applied research, and research with commercial ends is studied. Procurement, anti-trust, and patent policies, all of which affect the climate for private research and development, are examined.
Major first year accomplishments are summarized and plans are provided for the next 12-month period for a program established by NASA with the Environmental Research Institute of Michigan to investigate methods of making LANDSAT technology readily available to a broader set of private sector firms through local community colleges. The program applies a network where the major participants are NASA, university or research institutes, community colleges, and obtain hands-on training in LANDSAT data analysis techniques, using a desk-top, interactive remote analysis station which communicates with a central computing facility via telephone line, and provides for generation of land cover maps and data products via remote command.
Under the NASA-sponsored Energy Efficient Engine program, Pratt & Whitney Aircraft has successfully completed a comprehensive combustor rig test using a 90-degree sector of an advanced two-stage combustor with a segmented liner. Initial testing utilized a combustor with a conventional louvered liner and demonstrated that the Energy Efficient Engine two-stage combustor configuration is a viable system for controlling exhaust emissions, with the capability to meet all aerothermal performance goals. Goals for both carbon monoxide and unburned hydrocarbons were surpassed and the goal for oxides of nitrogen was closely approached. In another series of tests, an advanced segmented liner configuration with a unique counter-parallel FINWALL cooling system was evaluated at engine sea level takeoff pressure and temperature levels. These tests verified the structural integrity of this liner design. Overall, the results from the program have provided a high level of confidence to proceed with the scheduled Combustor Component Rig Test Program.
An analysis of the spatial phase and amplitude structures of the ground Pc 5 pulsations in the morning sector was carried out using data from the North American IMS magnetometer network. Signals in the X, Y, and Z components were found to propagate from noon to the nightside with an apparent phase velocity of 13 km/sec. The phase was determined to vary with latitude, with total latitudinal phase differences of 200 and 90 deg, respectively, for the X and Y components. Corresponding latitudinal phase differences in the vertical components were 550 deg for the Alaska chain, and 360 deg for the Fort Churchill chain. Phase variation in the Fort Churchill chain was attributed to the ionospheric Hall current related to the field line resonance and the earth induction current. The earth induction current in the shallower regions near Fort Yukon is a necessary factor to explain the large variation in the Alaska chain.
For three magnetically disturbed days in early 1980, data from south polar masses of the Magsat satellite are compared with data from search coil magnetometer, riometer, and photometer instrumentation at Siple, Antarctica. It is found that during each Magsat polar pass in the morning sector, the level of Pi 1 activity correlates well with the intensities of three-dimensional current systems. Fine structure is often observed in the field-aligned currents during periods of intense Pi activity. Among the Birkeland currents are 2-s to 10-s (16-80 km) structured perturbations; these are evident in the transverse components of the field and are thought to indicate filamentary currents. Pi 1 amplitudes are found to be considerably larger when region 2 Birkeland currents are overhead than when they are not. In one case, detailed features are identified in the high-resolution Magsat magnetic field data that may be current fluctuations related to asymmetric Pi 1.
Information which can be used in planning to insure commercial research and technology programs which are complementary to internally financed private sector activities are presented. The main concern is to identify the characteristics of productive projects in which firms are unlikely to invest. It is shown that: (1) if it is difficult to assess the commercial relevance of an R&D project or it it is characterized by high technical risk, or a relatively long payback period, private funding will be unlikely; and (2) if a project is large relative to the size of the firm, it is unlikely to be funded in the early stages of the R&D process. Firms tend to underinvest in projects with these characteristics.
The generation of available potential energy (APE) was evaluated in the warm sector of an extratropical cyclone containing intense convective activity. Mesoscale rawinsonde data from AVE-SESAME '79 was employed. Parametrization techniques were used for latent and sensible heating components, and variations for the Kuo scheme provided convective latent heat release. Radiative transfer models were used to obtain estimates of infrared and solar processes. The results indicated that solar heating was greater than IR cooling near midday. An extensive low-level cloud deck was the most radiatively active area. Negative generation of APE occurred during most of the period for the SESAME domain as a whole. The leading contributor was convective latent heating located primarily in regions of negative efficiency. Infrared cooling was the only component to consistently produce positive generation. Sensible heating provided an important sink of APE in the low levels during the afternoon.
Recognizing that gains in the cometary dust tail are electrically charged, the effect of an interplanetary sector boundary crossing on grain distribution is studied. Specifically, Halley's comet around the time of encounter by the GIOTTO and VEGA 1 and 2 spacecraft in March 1986 is considered. The smallest dust particles are strongly effected, and the projection of their distributions in a plane containing the sun-comet axis and normal to the orbital plane shows a wavy appearance. Also, since reversals in the interplanetary magnetic field occur with a periodicity of 5 to 10 days, the spacecraft, which follow 3 to 4 days apart, are likely to encounter entirely different dust distributions at the lower end of the mass spectrum.
Simultaneous data from the Chatanika radar and the DE 2 and NOAA 6 satellites are used to study the typical behavior of the winter evening-sector auroral plasma during moderate and steady magnetic activity. The equatorward edge of the auroral E layer, of the region 2 field-aligned currents, and of the region of intense convection are colocated. The auroral E layer extends several degrees south of the equatorward edge of the keV electron precipitation from the CPS. Although the main trough and ionization channel are embedded in a region of intense electric field where the plasma flows sunward at high speed, the flux tubes associated with these two features have different time histories. The midlatitude trough is located south of the region of electron precipitation, above a proton aurora. The ionization channel marks the poleward edge of the main trough and is colocated with the equatorward boundary of the electron precipitation from the central plasma sheet.
High-resolution magnetic field and charged-particle data acquired on March 25, 1986 by the Viking and DMSP-F7 satellites, as they traversed the dawn sector auroral zone on nearly antiparallel trajectories within 40 min of each oher, are analyzed. Magnetic field measurements by Viking at 0850 MLT and by DMSP at 0630 MLT indicate the presence of a large-scale earthward-directed region 1 Birkeland current and an upward-flowing region 2 current. Both satellites also observed a third Birkeland current adjacent to and poleward of the region 1 system with opposite flow. This poleward system is about 0.5 deg invariant latitude wide and has a current density comparable to the region 1 and 2 systems. The highest-latitude current is identified as region 0. Its charged-particle signatures were used to infer field line mapping to the equatorial plane.
Helium buffered floating-ring seals used in cryogenic turbopumps are subject to large temperature variations, shaft centrifugal growth, and dynamic shaft excursions. To prevent dangerous contact friction over a wide range of operating conditions generally requires liberal clearances with consequent high leakage. Reduction of helium consumption translates into lower space vehicle helium storage requirements and thus increased payload. A hydrostatic sectored floating-ring seal is described with self-adjusting clearance capabilities that enables the seal to operate with small clearances over the operating range to minimize leakage.
A Perkin Elmer MGA-1200, turbomolecular-pumped, magnetic sector, multiple gas analyzer mass spectrometer with modified inlet for fast response was characterized for the analysis of hydrogen, helium, oxygen and argon in nitrogen and helium background gases. This instrument was specially modified for the Vanderberg AFB SLC-6 Hydrogen Disposal Test Program, as a part of the Hydrogen Sampling System (H2S2). Linearity, precision, drift, detection limits and accuracy among other analytical parameters for each of the background gas were studied to evaluate the performance of the instrument. The result demonstrates that H2S2 mass spectrometer is a stable instrument and can be utilized for the quantitative analytical determination of hydrogen, helium, oxygen and argon in nitrogen and helium background gases.
The private sector economic and employment benefits (disaggregated among 80 industries and 475 occupations) of the proposed FY 1990 NASA procurement expenditures to the nation and to each state are estimated. Nationwide, it is found that FY 1990 NASA procurement expenditures of $11.3 billion will have an economic multiplier of 2.1 and will create, directly and indirectly, 237,000 jobs, $23.2 billion in total industry sales, $2.4 billion in corporate profits, and $7.4 billion in Federal, state, and local government tax revenues. These benefits are widely dispersed throughout the United States and are significant in many states not normally considered to be major beneficiaries of NASA spending. The indirect economic benefits are identified for each state resulting from the second-, third-, and fourth rounds of industry purchases generated by NASA procurement expenditures. Each state is ranked on the basis of several criteria, including the total benefits, indirect benefits, and per capita benefits received from NASA spending. The estimates developed are important for maintaining a viable U.S. Space Program through the remainder of this century.
Magnetic-field and medium-energy particle data from the AMPTE/CCE spacecraft are used to study substorm-associated ULF pulsations in the midnight sector at a radial distance of 8 to 9 earth radii. The particle data are used to identify ion injections and to detect the electric field of ULF waves. A case study of the events on May 23, 1985 shows that the waves have the properties of a fundamental-mode standing Alfven wave. It is suggested that these observations are evidence of substorm-associated standing Alfven waves in the nightside magnetosphere.