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Graphs of the gradient components (negative electric field components) recorded on three airplanes, at Kennedy Space Center, Florida are presented.
An ultraviolet spectral atlas is presented for the B0 V star, Tau Scorpii. It has been scanned from 949 to 1560 A by the Princeton spectrometer aboard the Copernicus satellite. From 949 to 1420 A the observations have a nominal resolution of 0.05 A. At the longer wavelengths, the resolution is 0.1 A. The atlas is presented in both tables and graphs.
The first of two solar occultations of the satellite Helios-1 in 1975 occurred in April when the satellite's ray path approached the west limb of the sun to a minimum distance of 1.63 solar radii. The second occultation took place in late August/early September when Helios-1 was totally eclipsed by the photosphere. Measurements of the polarization angle of the linearly polarized telemetry signal were performed with automatic tracking polarimeters at the 64 m Goldstone Tracking Station in California and also at the 100 m radio telescope in Effelsberg, West Germany. The coronal Faraday rotation as a function of the solar offset for both occultations is shown in graphs. The theoretical significance of the observations is investigated.
The reflection of sound at an interface between two fluid half-space in relative motion (one in motion and the other at rest), but with different density and different sound speed, is considered. The reflection coefficient is found in an explicitly closed form. A brief discussion of the effect of mean velocity, i.e., corresponding Mach number on different noise generating quadrupole directivities concludes the presentation of the paper. The graphs provided illustrate this aspect in a rather more convincing way.
In aircraft and satellite multispectral scanner data, soil background signals are superimposed on or intermingled with information about vegetation. A procedure which accounts for soil background would, therefore, make a considerable contribution to an operational use of Landsat and other spectral data for monitoring the productivity of range, forest, and crop lands. A description is presented of an investigation which was conducted to obtain information for the development of such a procedure. The investigation included a study of the soil reflectance that supplies the background signal of vegetated surfaces. Landsat data as recorded on computer compatible tapes were used in the study. The results of the investigation are discussed, taking into account a study reported by Kauth and Thomas (1976). Attention is given to the determination of Kauth's plane of soils, sun angle effects, vegetation index modeling, and the evaluation of vegetation indexes. Graphs are presented which show the results obtained with a gray mapping technique. The technique makes it possible to display plant, soil, water, and cloud conditions for any Landsat overpass.
In connection with proposals for a second generation shuttle vehicle it has been suggested that the engine regenerative coolant be the oxidizer rather than a fuel. The feasibility of such an approach depends on the suitability of oxygen for the cooling functions. The information currently available concerning the heat transfer characteristics of liquid oxygen (LOX) in the near critical region at elevated pressures is not sufficient for an evaluation. It is, therefore, proposed to make use of data from similar fluids for a simulation of the heat transfer characteristics of LOX. Graphs are presented which demonstrate that experimental heat transfer results for fluid nitrogen can be used qualitatively to simulate heat transfer to liquid oxygen. Quantitative agreement appears satisfactory provided the proper level or adjusting constant can be determined.
An investigation was conducted of the two reactions: Sc + F2 yields ScF(asterisk) + F and Y + Cl2 yields YCl(asterisk) + Cl. Experiments were designed for studying the reactions under the relatively high pressure conditions (5-20 torr) appropriate for chemical laser operation. A shock tube was used to provide a short duration flow through a supersonic nozzle array. Shock wave heating is used to dissociate the ScCl3 or YCl3 at temperatures of about 6000 K, before the gases are accelerated and expanded through the supersonic nozzle array. The expanded primary flow is then mixed with a secondary flow of F2 introduced through slots at the trailing edge of each nozzle blade. Graphs show the temporal behavior of the visible spontaneous emission over the range from 3000 to 9000 A for a typical test condition, a microdensitometer tracing of the visible emission over the range from 4000 to 7000 A, and the spontaneous emission from ScF(asterisk) obtained by computer image processing of intensity data.
Viking Orbiter-1 (VO-1) made a series of close flybys of the Martian satellite Phobos in February and May 1977. A description is presented of the results obtained during the flybys in February. The flyby geometries for the encounter period in February are shown in a graph. The trajectory design gave flybys on the illuminated side of Phobos within 80 to 300 km during the entire encounter period. The primary encounter observations of Phobos included visual and infrared imaging as well as radio tracking of VO-1 while it was under the gravitational influence of Phobos. Visual imaging was obtained from two narrow-angle television cameras. Infrared observations were obtained from an infrared thermal mapper. Radio data included S- and X-band Doppler and ranging data to VO-1 with a 10-second Doppler count. Assuming for Phobos a volume of 500 + or - 900 cu km, a mean density of 1.9 + or - 0.6 g/cu cm is obtained for it on the basis of the processed data.
A description is presented of the results of a computer simulation involving a study of the particle precipitation induced by coherent VLF waves in the magnetosphere. The results of a computation for a 10 picoweber/sq m wave amplitude are shown in a graph. The precipitated flux for three different energies is given in a table. For 1.5 keV the energy deposition rate is about 0.8 erg/sq cm-sec, almost as intense as a moderate aurora. It is concluded that significant energy is deposited by a wave of 10 picoweber/sq m intensity. Such a wave amplitude is representative of highly coherent VLF wave types that are found in the magnetosphere. On the basis of the considered results it appears that controlled VLF wave injection in the magnetosphere could be an important and useful tool to study the coupling processes between the atmosphere and magnetosphere.
The atomic nitrogen in the thermosphere, which is produced either in its ground term or in a highly reactive metastable term, reacts with molecular oxygen to form nitric oxide and atomic oxygen. However, nitric oxide is destroyed in reactions with atomic nitrogen in which molecular nitrogen and atomic oxygen is formed. Adopted reactions and rate coefficients for odd nitrogen chemistry are listed in a table. An analysis is conducted of the temperature distribution below 150 km and its effect on the odd nitrogen chemistry. The latitudinal distribution of nitric oxide is discussed. Satellite measurements have shown that nitric oxide concentrations at high latitudes are highly variable in both time and space. Their average concentrations are 3-4 times higher than at mid-latitudes. The measured variation of nitric oxide density as a function of latitude is shown in a graph.
The detection of transitions in NH2D at 85926.2 and 110153.4 MHz from the Orion molecular cloud is reported. An 11-m radio telescope with an 80-120 GHz cooled Cassegrain receiver and a tunable quasi-optical rejection filter was used in the investigations. Equations of statistical equilibrium for the lowest 34 energy levels of NH2D were solved. It seems unlikely that the observed lines arise in the very extended CO cloud. However, they could originate either in the molecular 'ridge' or the unresolved (Kleinmann-Low) core of the cloud or both. A column density of about 50 trillion/sq cm is deduced. The NH2D spectra, with 1 MHz resolution, are shown in a graph. Using previously reported column densities for NH3, a value of 0.05 with an estimated maximum uncertainty factor of 10 is found for the ratio NH2D/NH3.
A computer simulation is applied to the production of strong electric potential double layers (DL) in a triple plasma device. The simulation is intended to represent DL in the low magnetosphere above the auroral zones. The DL are described as standing electrostatic shocks with different energy coefficients in their strong and weak forms. The strong DL was generally found to be unstable, but stability could be imparted if a population of trapped electrons was presented. Stability increased with the length of the system. A schematic for the system is presented, and a phase-space plot of electrons (indicating system stability) is graphed.
The concept of single stage earth-to-orbit transportation is studied with respect to existing and projected ramjet technology. Four types of ramjet are analyzed: fan ejector, fan ramjet, supersonic combustion ramjet, and fan ramjet with turbojet boosters. A fan ramjet with a removable fan, with separate rockets for the non-air-breathing flight phase, is considered superior to an ejector ramjet, for both ease of orbit insertion and payload boost capability. Vehicle design is also discussed in terms of trajectory integration and optimization, aerodynamic trim and stability, and complete mass estimation. Graphs are presented showing Mach number for air-breathing and non-air-breathing flight, specific impulse from various ramjet engines, and orbital-insertion parameters.
Energy consumption for the developed and non-developed world is expressed as a function of GNP. An almost straight-line graph results when energy consumption statistics are treated in this manner. The richest countries consume the most energy, and the poorest countries the least. It therefore follows that greater energy production in the developing countries (leading to greater energy consumption) will contribute to their economic growth. Energy resources in the developing countries are compared, including: solid fossil fuels, crude oil, natural gas, oil shale, and uranium. Mention is also made of the potential of renewable energy resources, such as solar, wind, and hydroelectric power, in the underdeveloped world; and it is these resources which offer the greatest possibilities for economic improvement if the money is forthcoming, i.e., from the world bank, to fund the necessary technology.
A quantitative investigation is conducted concerning the effect of TiO opacities on the atmospheric temperature structure in late-type stars. Model atmospheres are computed, taking into account opacity-sampling (OS) or straight-mean (SM) opacities for three singlet and three triplet band systems of TiO. Model atmospheres using OS and SM opacities for TiO are compared with models having no TiO, giving attention to the effects of TiO opacities on the temperature structures of various atmospheres and the usefulness of straight-mean TiO opacities in model atmosphere calculations. The results of the model-atmosphere calculations are presented in two graphs. TiO opacities produce a global atmospheric heating which may reach several hundred kelvins. It is shown quantitatively that the TiO molecule is an important source of atmospheric opacity in cool stars of solar composition. The relative importance of TiO opacities to the thermal structure of a stellar atmosphere is influenced in the outer layers by CO and H2O cooling effects and in the deeper layers by CO, CN, and metal line absorption.
Measurements have been conducted of the effect of the convection of ions and electrons on the discharge characteristics in a large scale laser. The results are presented for one particular distribution of ballast resistance. Values of electric field, current density, input power density, ratio of electric field to neutral gas density (E/N), and electron number density were calculated on the basis of measurements of the discharge properties. In a number of graphs, the E/N ratio, current density, power density, and electron density are plotted as a function of row number (downstream position) with total discharge current and gas velocity as parameters. From the dependence of the current distribution on the total current, it appears that the electron production in the first two rows significantly affects the current flowing in the succeeding rows.
An earth-based evaluation of the Viking Lander 1 life-detection experiments was conducted using a radiofrequency glow discharge in a simulated Martian atmosphere. The Gas Exchange Experiment conducted in the humid mode released substantial amounts of CO2, O2, N2, Ar, and CO into the atmosphere, indicating that these substances were adsorbed onto the Martian soil. An adsorption potential plot is given, graphing quantity of gas against time (d). For a model surface area of 17 squares meters per gram of measured substance, oxygen adsorption was found to be relatively high, a result which tends to confirm the hypothesis that Martian oxygen exists largely in chemisorbed states or in active oxygen compounds, e.g., peroxide, superoxide, hydroperoxide
According to the propulsion concept of solar sail spacecraft the thrust force is produced by the specular reflection of sunlight from a large, essentially flat, reflecting surface. The magnitude of this force is approximately 9 newtons for a perfectly reflecting sail with an area of 1 square kilometer oriented normal to the sunline at a distance of one astronomical unit from the sun. There exists a restriction in the types of orbit transfer trajectories which can be considered with this propulsion system. In the case of the second propulsion system being considered for the Halley's comet rendezvous mission, thrust is produced by the acceleration of ionized mercury atoms by an electric field. Power to the ion thrusters is supplied by lightweight solar arrays which can provide up to 100 kW of electrical power at a distance of 1 AU from the sun. Because of differing thrust constraints for the two propulsion systems, trajectories for a Halley's comet rendezvous mission are significantly different for the Ion Drive and Solar Sail spacecraft. Details concerning the trajectory characteristics are shown with the aid of a number of graphs.