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At least 1,081 records · Page 60
All sourcesNASA NTRSDOE OSTI
NASA NTRS1970

User oriented data processing at the University of Michigan

The multispectral techniques have shown themselves capable of solving problems in a large number of user areas. The results obtained are in some instances quite impressive. In many instances, the multispectral detection of various phenomena is an empirical fact for which there is little physical explanation today. To date, most of the user applications that have been addressed are exploratory in nature. The closest approximation to an operational situation encountered so far is that of the survey of wetlands in North Dakota reported in this paper.

Thomson, F. J.↗
NASA NTRS1971

NASA multidisciplinary research grant

Research is discussed in the multidisciplinary areas of space and planetary science; materials and radiation; systems, instrumentation, and structures; and technology and man. Highlights are identified as an alpha-recoil track method of archeological dating; infrared astronomical telescope; reaction rates data, semiconductor radiation detectors, and analysis of time-dependent systems; Gunn effect devices for microwave generation and detection, mode-locked lasers, and radiation theory; and the application of a satellite communication system to educational development. Detectors to be flown on Apollo 16 to measure heavy particle flux in the solar wind and to be part of the HEAO-A experiment on extremely heavy nuclei in cosmic rays were developed. The impact of the multidisciplinary research on university activities is described, and individual departmental reports are included.

Source record↗
NASA NTRS1971

System Definition Phase and Acquisition Phase Project Plan for Small Astronomy Satellite SAS-D

This Project Plan for the Small Astronomy Satellite (SAS-D) is Goddard Space Flight Center's plan for accomplishing the project. It is issued in compliance with NASA Handbook NHB 7121.2 and NMI 7120.1, dated May 4, 1970, Subject: Approval and Implementation of Office of Space Science and Applications (OSSA) Research and Development (R&D) Projects. The Project Plan, as approved by GSFC executive management and NASA Headquarters, is the project manager's charter and defines his specific plan of action. System definition phase activities of the SAS-D Project will be a continuation of the analytical work that established the overall feasibility of the project. The system concept derived from that analytical work is defined in the Phase A (Mission Definition Phase) technical report. System definition phase activities will include detailed engineering analysis and preliminary breadboarding necessary to establish a single project approach from the feasible approaches. This document will be revised at the end of the system definition phase to provide greater detail on acquisition phase planning and to specify a specific system design.

Donald A Krueger↗
NASA NTRS1971

Saturn component failure rate and failure rate modifiers

Failure mode frequency ratios, environmental adjustment factors, and failure rates for mechanical and electromechanical component families are presented. The failure rates and failure rate modifiers resulted from a series of studies whose purpose was to provide design, tests, reliability, and systems engineers with accurate, up-to-date failure rate information. The results of the studies were achieved through an extensive engineering analysis of the Saturn Program test data and Unsatisfactory Condition Reports (UCR's) and the application of mathematical techniques developed for the studies.

Source record↗
NASA NTRS1971

The kinetics of crystallization of molten binary and ternary oxide systems and their application to the origination of high modulus glass fibers

Emphasis on the consideration of glass formation on a kinetic process made it possible to think of glass compositions different from those normally employed in the manufacture of glass fibers. Approximately 450 new glass compositions were prepared and three dozen of these compositions have values for Young's modulus measured on bulk specimens greater than nineteen million pounds per square inch. Of the new glasses about a hundred could be drawn into fibers by mechanical methods at high speeds. The fiber which has a Young's modulus measured on the fiber of 18.6 million pounds per square inch and has been prepared in quantity as a monofilament (to date more than 150 million lineal feet of 0.2 to 0.4 mil fiber have been produced). This fiber has also been successfully incorporated both in epoxy and polyimide matrices. The epoxy resin composite has shown a modulus forty percent better than that achievable using the most common grade of competitive glass fiber, and twenty percent better than that obtainable with the best available grade of competitive glass fiber. Other glass fibers of even higher modulus have been developed.

Bacon, J. F.↗
NASA NTRS1971

Ion microprobe mass analysis of lunar samples. Lunar sample program

Mass analyses of selected minerals, glasses and soil particles of lunar, meteoritic and terrestrial rocks have been made with the ion microprobe mass analyzer. Major, minor and trace element concentrations have been determined in situ in major and accessory mineral phases in polished rock thin sections. The Pb isotope ratios have been measured in U and Th bearing accessory minerals to yield radiometric age dates and heavy volatile elements have been sought on the surfaces of free particles from Apollo soil samples.

Anderson, C. A.↗
NASA NTRS1971

Detection techniques for tenuous planetary atmospheres

The development of new types of detectors for analysis of planetary atmospheres is discussed. Initially, the interest was in detectors for use under partial vacuum conditions. The program has been extended to include detectors for use at one atmosphere and adsorption system for control and separation of gases. Results to date have included detectors for O2 and H2 under partial vacuum conditions. Experiments on detectors for use at high pressures began in 1966, and systems for CO, H2, and O2, were reported. Electrically controlled adsorbent was developed. It was demonstrated that under proper conditions a thin film of semiconductor material could be electrically cycled to adsorb and desorb a specific gas. This work was extended to obtain quantitative data on the use of semiconductors as controllable adsorbents.

Hoenig, S. A.↗
NASA NTRS1971

Mission definition study for Stanford relativity satellite. Volume 1: Systems and program

The objective of the relativity satellite mission is to perform an experiment in which a gyroscope in motion about the earth undergoes precession, presumably relativistic, with respect to the fixed stars. Performance of this experiment would clearly test the general theory of relativity and its various modifications. This is the only experiment suggested to date which would confirm the existence of motional drift as well. A mission is defined in which the measurement of the geodetic effect term to 0.2 arc sec/yr is achievable and the measurement of both geodetic and motional drift terms to an accuracy of 0.001 arc sec/yr may be possible. The design of the flying dewar satellite needed to maintain the experiment at cryogenic temperatures is discussed. The gyroscopes, magnetometer, and optical contacting method for dimensional stability of the experimental assembly are considered.

Source record↗
NASA NTRS1972

A modular approach for assessing the effect of radiation environments on man in operational systems. The radiobiological vulnerability of man during task performance

A modular approach for assessing the affects of radiation environments on man in operational systems has been developed. The feasibility of the model has been proved and the practicality has been assessed. It has been applied to one operational system to date and information obtained has been submitted to systems analysts and mission planners for the assessment of man's vulnerability and impact on systems survivability. In addition, the model has been developed so that the radiobiological data can be input to a sophisticated man-machine interface model to properly relate the radiobiological stress with other mission stresses including the effects of a degraded system.

Ewing, D. E.↗
NASA NTRS1971

Spacecraft cryogenic gas storage systems

Cryogenic gas storage systems were developed for the liquid storage of oxygen, hydrogen, nitrogen, and helium. Cryogenic storage is attractive because of the high liquid density and low storage pressure of cryogens. This situation results in smaller container sizes, reduced container-strength levels, and lower tankage weights. The Gemini and Apollo spacecraft used cryogenic gas storage systems as standard spacecraft equipment. In addition to the Gemini and Apollo cryogenic gas storage systems, other systems were developed and tested in the course of advancing the state of the art. All of the cryogenic storage systems used, developed, and tested to date for manned-spacecraft applications are described.

Rysavy, G.↗
NASA NTRS1972

Aerodynamic characteristics of several launch configurations utilizing the Titan 3 L booster and MMC DTO-7 Orbiter

The .00429 scale model Titan 3 booster was mated with the DTO-7 space shuttle orbiter with drop tanks and tested for aerodynamic performance in a 14 x 14 inch trisonic wind tunnel. Six component aerodynamic force and moment data were measured on several variations of the above component in a launch configuration over a Mach number range from 0.6 to 3.48. Angle of attack ranged from -12 deg to 12 deg at 0 deg and -6 deg sideslip angle and sideslip angle ranged from -12 deg to 12 deg at 0 deg angle of attack. Date are presented in plotted form in both the stability and body axis system.

Michna, D. J.↗
NASA NTRS1972

Investigations of lunar materials

The investigations were directed at determining the radiation history and surface chronology of lunar materials using the etched particle track technique. The major lunar materials studied are the igneous rocks and double core from Apollo 12, the breccia and soil samples from Apollo 14, and the core samples from Luna 16. In the course of this work two new and potentially important observations were made: (1) Cosmic ray-induced spallation-recoil tracks were identified. The density of such tracks, when compared with the density of tracks induced by a known flux of accelerator protons, yields the time of exposure of a sample within the top meter or two of moon's surface. (2) Natural, fine scale plastic deformation was found to have fragmented pre-existing charged particle tracks, allowing the dating of the mechanical event causing the deformation.

Comstock, G. M.↗
NASA NTRS1972

Status of Langley studies of aerodynamics and interference effects of tandem launch vehicles

Some of the aerodynamic and interference effects measured from wind-tunnel tests of three fully reusable space shuttle configurations at transonic and low-supersonic speeds are presented, and the status is given of an assessment of the analytical approach to date. The three configurations tested were a low-fineness-ratio booster combined in tandem with a delta-wing orbiter, designated the "low-fineness-ratio configuration,' and a phase B shuttle configuration consisting of the delta-wing orbiter and high-fineness-ratio booster, designated the "stage-arrangement configuration,' arranged in tandem and in parallel. The force measurements obtained at a Mach number of 1.5 for the low-fineness-ratio configuration were representative of the transonic and low-supersonic speed ranges where the interference effects are predominant and were used for comparison with values calculated at the same Mach number. This comparison is the basis for a preliminary assessment of the initial application of the analytical approach.

Scallion, W. I.↗
NASA NTRS1972

Preliminary geologic map of the region around the candidate Proclus Apollo landing site, part J

The Proclus Crater region was mapped to test the value, for photogeologic mapping purposes, of Apollo 15 metric photographs and to estimate the scientific value of the area as a potential landing site. Adjacent frames of the metric photography were overlapped with the base frame to provide stereographic images. Because of the high quality of the photographs, it was found that the geologic units could be more definitely interpreted and dated than those of earlier maps. The photographs tend to confirm the earlier interpretation of the rugged area as composed of bedrock uplifted when the Crisium basin formed. They also suggest that an earlier predominantly volcanic interpretation of the terra in this area might be replaced by an interpretation in which mass wasting and fracturing play the major roles in producing different terrain types. It was concluded that because of apparent lithologic homogeneity, the terra of the Proclus region is an undesirable objective for an extensive manned lunar landing mission.

Wilhelms, D. E.↗
NASA NTRS1972

Aerodynamic stability and drag characteristics of a parallel burn/SRM ascent configuration at Mach numbers from 0.6 to 4.96

Experimental aerodynamic investigations were conducted in the NASA/MSFC 14-inch trisonic wind tunnel during March 1972 on a .003366 scale model of a solid rocket motor version of the space shuttle ascent configuration. The configuration consisted of a parallel burn solid rocket motor booster on an external H-O centerline tank orbiter. Six component aerodynamic force and moment date were recorded over an angle of attack range from -10 to 10 deg at zero degrees sideslip and over a sideslip range from -10 to 10 deg at 0, +6, and -6 deg angle of attack. Mach number ranged from 0.6 to 4.96. The performance and stability characteristics of the complete ascent configuration and build-up, and the effects of variations in tank diameter, orbiter incidence, fairings and positioning of the solid rocket motors and tank fins were determined.

Sims, J. F.↗
NASA NTRS1972

Circuit performance of a parasitic-loading digital speed controller for a 400-hertz turbine-driven alternator

Parasitic speed controllers are used in space power electrical generating systems to maintain the speed of the turbine-driven alternators within specified limits. Selected subcircuits for a solid state parasitic-loading speed controller were assembled and tested. The test results as obtained to date consist of the performance evaluation of the frequency reference and the period counter subcircuits. These circuits performed as expected.

Ryan, J. P.↗
NASA NTRS1971

Spaceborne clock system: Some alternatives for a proposed NASA experiment

A spaceborne clock experiment is proposed with the objectives of improving international time and frequency comparisons, studying precise one-way Doppler tracking and one-way ranging techniques, performing relativistic studies, and developing new atomic frequency standards technology. Various alternatives are considered for accomplishing these goals, including the use of existing satellite and earth-based time dissemination systems as well as the development of a new frequency standard for this specific application. One conclusion is that several attractive alternatives already exist for meeting the goal of improved time and frequency dissemination. However, to achieve all the other 4 goals at the NASA-stated levels of accuracy, a spaceborne atomic frequency standard may be required. An analysis of achievements to date with quartz oscillators, rubidium standards, cesium beam standards, hydrogen masers, and several other possibilities leads to the conclusion that cesium and rubidium standards offer the best choices for the experiment as proposed by NASA. The greatest obstacle to a spaceborne atomic standard appears to be its electrical power requirements.

Beehler, R. E.↗
NASA NTRS1972

A compilation of laboratory spectra

An up-to-date listing of the spectra obtained in the spectroscopy laboratory and a complete description of the experimental conditions are presented.

Margolis, J. S.↗