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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Early nausea and vomiting response of swine to ionizing radiation related to radiation dosage and effect on humans in space missions
Free radical destruction by gamma irradiation in organic solids at low temperature measured by electron spin resonance spectroscopy, noting dosage relationship
Crew radiation dosage from fission fragments in plume from gas core nuclear rocket
Dosimeter determines time-integrated radiation dosage to which an individual is exposed. Integration is measured chemically in proportion to radiation detected. Wearer receives an exposure measurement representing an average of the dose over the entire body.
Predicted radiation dosage for Mars lander mission
Criteria and procedures for determining dosage of penetrating space radiation and design of appropriate protection for space vehicles
Determining solar absorptance stability of metallized Teflon second surface mirror thermal control coatings as function of electron, proton, and UV radiation dosage
Calculation of crew radiation dosage from uranium gas nuclear rocket engine exhaust backflow of fission products
Heavy cosmic particle dosage measurement by chemical etching of particle tracks on Apollo astronauts plastic helmets
Computerized human body anatomical geometrical model with life size skeleton and organs scaling for radiation dosage analyses in space missions
Radiation tests were conducted on the various types of Skylab film to establish the total radiation dosages compatible with an acceptable level of film fogging, and on the S190 borosilicate window to establish radiation limits for an acceptable darkening level. The results verified that most of the films would be unusable when returned to earth, and that the borosilicate window would be darkened beyond allowable limit, unless additional protection was provided. The operational solutions to these problems involve protecting the film with five film vaults and protecting the window with a radiation shield. The largest vault is made of aluminum and weighs over 2000 lb (its thickest compartment wall is 3.4 in.). The window radiation shield is a light honeycomb structure which is swung away for limited astronaut viewing or when the S190 experiment is in operation. Although the shield is light weight, it is heavy enough to stop the large number of low energy electrons making up a major part of the external environment and which are potentially damaging to the window. A brief description is given of the Skylab mission and some of the associated experiments. The radiation environment the spacecraft will encounter is discussed.
The initial and growth modular space station configurations are described, and the evolutionary steps arriving at the final configuration are outlined. Supporting tradeoff studies and analyses such as stress, radiation dosage, and micrometeoroid and thermal protection are included.
Investigation of the importance of chain-scission processes and of the applicability of the general theory of network formation to polyethylene with respect to critical conditions for gelation, using molecular weight fractions of linear polyethylene irradiated at 133 C. The partitioning between sol and gel was found to adhere to the theory just beyond the gel point. Deviations from theory occurred as the irradiation dosage was increased. It was concluded that main-chain scission at the temperatures concerned is not a significant process.
NASA is in the process of conducting a broad program of research and development of technology to qualify, support, and permit the successful use of man in long-term space flight. The technological tasks include human engineering, extravehicular engineering, life support, and human research to assess the effect of space stresses on human physiology and psychology. Various testing techniques that are being used may have future relevance to world health. These include a biocybernetic approach to the study of cardiovascular stresses, measurement of blood flow by means of the Doppler effect, and a device for simulating radiation dosages similar to those produced in solar flares. The planned program includes a study of both humans and animals.
The principal questions about the derivation of the lunar surface have not yet been settled: is it the surface left over from the process of accumulation of the moon, or is it a surface generated by magmatic processes on the moon and subsequently altered by further infall from outside. The evidence derived from many sources now favors the former. Seismic data suggest an absence of bedrock down to a depth of several kilometers, and instead a compacted powder only. The 'mascon' evidence can be understood as a consequence of major impacts in a deep porous layer. The great abundance of cosmic ray tracks in most soil samples demands a much greater cosmic ray dosage than present rates would cause in the age of the moon, unless the dust represented infallen material previously irradiated.
Emission into the atmosphere of aerospace vehicle exhaust effluents and by-products is considered by using atmospheric diffusion models to calculate downwind concentrations and dosages from various engine and solid rocket booster (SRB) exhaust by-products. A major effort is being made to gather detailed data on the chemical reactions that take place between the exhaust effluents and the atmosphere. Basic diffusion estimation formulas consider normal exhaust releases, abnormal releases, leaks, and inadvertent spills. Cloud rise formulas for use in source identification are included and meteorological inputs covered.
Simultaneous observations by identical ionization chambers aboard the satellites OGO-1 and OGO-3 are utilized to investigate spatial variations in particle intensity near and inside the magnetosphere during the solar cosmic ray events of September 1966. Cross-correlation of the absolute proton flux computed from the chamber rate during three solar particle events shows good agreement with the measurements by the IMP-F Solar Proton Monitor during the same events. The chamber has a dynamic range of over six orders of magnitude. Before launch it was calibrated in the laboratory with radiation dosages in the range 1 R/hr-6000 R/hr. The OGO-1 and OGO-3 chambers, which were normalized in the laboratory prior to the launch, are found to maintain their normalization within approximately equal to 1 per cent during their flight. The high sensitivity and absolute inter-comparability of the instruments allow small intensity differences to be detected and it is established that the observed differences can be explained by a magnetospheric screening effect when an anisotropic beam of particles is present in space. Evidence is presented to show that the screening is at times complete for a duration of as much as 110 min in the tail of the magnetosphere so that during this period the solar cosmic rays (E approximately equal to 15 MeV) have virtually no access to that region of the magnetosphere. Small intensity fluctuations of a temporal nature observed and found to be subjected to a damping effect inside the magnetosphere.
Three areas of research in NASA'S University Program are described. Primitive terrestrial living cells were studied as a guide to the kind of cells to look for in extraterrestrial life. Experiments in zero gravity conditions are described with emphasis upon effects on small organisms. The effects of ionizing radiation on cells are studied so that it will be possible to predict dosages which can be tolerated by humans with no permanent damage.