25,270 research outputs found

    A study of Kapton degradation under simulated shuttle environment

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    A system was developed which employs a source of low energy oxygen ion to simulate the shuttle low Earth orbit environment. This source, together with diagnostic tools including surface analysis ans mass spectroscopic capability, was used to measure the dependence of ion energy of the oxygen induced CO signals from pyrolytic graphite and Kapton. For graphite the CO signal was examined at energies ranging form 4.5 to 465 eV and for Kapton from 4.5 to 188 eV. While the relative quantum yields inferred from the data are reasonably precise, there are large uncertainties in the absolute yields because of the assumptions necessary to covert the measured signal strengths to quantum yields. These assumptions are discussed in detail

    Oxygen interaction with space-power materials

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    Data from the space shuttle flights have established that many materials experience relatively rapid degradation when exposed to the low Earth orbit ambient atmosphere, which is predominately atomic oxygen. While much was learned from samples flown on the shuttle, laboratory simulations of the shuttle environment are necessary for a detailed understanding of the various interactions which contribute to the observed degradations. These laboratory experiments are particularly important for predicting the deterioration to be expected for materials aboard orbiting power systems, which will be exposed for long periods of time and could have components operating at very high temperatures. By using a mass spectrometer to synchronously detect molecules emitted from the surface as a result of amplitude modulated oxygen ion bombardment, quantum yields were obtained as a function of ion energy. A technique was developed to obtain preliminary yield data by slowly scanning the mass setting of the mass spectrometer; measurements were extended down to zero modulation frequency; yield data was obtained for the insulating materials (Nomex, Kevlar, and Teflon) used in the construction of electrodynamic tethers; a heated sample holder was constructed to investigate the effect of sample temperature on quantum yields; and the instrumentation was developed to observe the mass spectrometer signal as a function of time during and following bombardment of the sample by a brief (approximately 1 millisecond) pulse of ions

    The aerospace technology laboratory (a perspective, then and now)

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    The physical changes that have taken place in aerospace facilities since the Wright brothers' accomplishment 78 years ago are highlighted. For illustrative purposes some of the technical facilities and operations of the NASA Lewis Research Center are described. These simulation facilities were designed to support research and technology studies in aerospace propulsion

    S-cubed-a spacecraft and experiment description

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    The launch of the Explorer 45 satellite and the instruments installed in the satellite are discussed. The scientific objectives of the first mission, the orbital parameters, and the capabilities of the data system are examined. The satellite is designed to carry out investigations of specific magnetospheric phenomena in the heart of the magnetosphere. The data handling system is programmable from the ground for greater flexibility

    Development of a cobalt-tungsten ferromagnetic, high-temperature, structural alloy

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    Cobalt-tungsten ferromagnetic, high temperature structural alloy for rotor applications in space power generator

    Effect of environment on biological burden during spacecraft assembly

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    Determining effects of environment on accumulation of biological burden on spacecraft during assembl
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