Photometric studies of composite stellar systems. II - Observations of H2O absorption and the coolest stellar component of E and S0 galaxies
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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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Surface and airborne field measurements of the cloud behavior and effluent dispersion from a solid rocket motor launch vehicle are presented. The measurements were obtained as part of a continuing launch vehicle effluent monitoring program to obtain experimental field measurements in order to evaluate a model used to predict launch vehicle environmental impact. Results show that the model tends to overpredict effluent levels.
A program listing for a finite element computer code for the analysis of mantle convection is provided.
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The design realization, evaluation and modelling (DREAM) system is evaluated. A short history of the DREAM research project is given as well as the significant characteristics of DREAM as a development environment. The design notation which is the basis for the DREAM system is reviewed, and the development tools envisioned as part of DREAM are discussed. Insights into development environments and their production are presented and used to make suggestions for future work in the area of development environments.
The External Tank (ET) is the structural backbone of the Space Shuttle. The ET is discussed relative to its role; its design as a highly efficient Shuttle element; the liquid oxygen tank - a thin shelled monocoque; the intertank - the forward structural connection; the liquid hydrogen tank structure - the connection with the Orbiter; the ET structural verification; the propulsion system - a variety of functions; the electrical subsystem; electrical subsystem qualification; the thermal protection system; and other related problems. To date the qualification programs have been extremely successful and are almost complete, and the first flight tank has been delivered. Tomorrow's objectives will concentrate on establishing the facilities, tools and processes to achieve a production rate of 24 ETs/year.
A study of nitrous oxide formation mechanisms indicates that N2O concentrations greater than 10 to the 9th per cu cm could be produced in IBC III aurora or by lower-level activity lasting for many hours, and, in favorable conditions, the N2O concentration could exceed the local nitric oxide density. An upper limit on the globally averaged N2O production rate from auroral activity is estimated at 2 x 10 to the 27th per second.
Heat Capacity Mapping Mission (HCMM) in the form of an apparent thermal inertia image were merged with shaded relief maps and Bouguer gravity maps. The HCMM data show that the dominant structural grain in Missouri strikes in a northwesterly direction. The strike is the same as a major basement fault or flexure identified on the basis of gravity images.
Day-IR, day-visible, and night-IR image data sets were analyzed. All three images were contrast enhanced, using a linear stretch. The night-IR image was destriped using a box-car filtering approach. Apparent thermal inertia images were generated from the data. The enhanced data and the apparent thermal inertia image were also registered and overlayed onto shaded relief images depicting topography and onto a colored version of the Missouri geologic map. The combination of the apparent thermal inertial image and the shaded relief map proved to have the greatest discriminability in terms of portraying linear features. The reason seems to be that the vegetation canopy on the Ozark Plateau is different topography, tend to emphasize subtle topographic effects.
Electron density profiles from ground-based and rocket-borne measurements conducted at three sites in northern Scandinavia under various degrees of geophysical disturbances are presented. These data are checked against an instantaneous picture of the ionospheric absorption obtained via the dense riometer network. A map of the riometer absorption and measured electron densities over Scandinavia is given.
A petrologic and electron-probe study of enstatite in six EH3, 4, and 5 chondrites, including the previously undescribed Allan Hills A77156, provides no support for Leitch and Smith's (1982) model in which crystals and liquids from two chemically distinct, partially molten planetesimals are mixed. It is found that Cr and Mn concentrations in enstatite grains in matrix and chondrules are not uniquely defined by their cathodoluminescence color. Wide variations in enstatite compositions among chondrules may partly reflect heterogeneities in the precursor material. However, correlated variations of Cr, Mn, and Fe concentrations in enstatite are probably largely due to fractionation during chondrule crystallization. The inverse correlation of petrologic type with minor element concentrations in enstatite appears to be a metamorphic effect.
The longitudinal shower development of extensive air showers (EAS) observed in the fly's eye is used to determine the distribution of X sub max, the depth in the atmosphere of the EAS maximum. Data and Monte Carlo simulations of proton and iron primaries are compared. A substantial contribution from light primaries is noted.
The anisotropy of cosmic rays observed by the Utah Fly's Eye detector has been studied. Emphasis has been placed on examining distributions of events in galactic coordinates. No statistically significant departure from isotropy has been observed for energies greater than 0.4 EeV (1 EeV = 10 to the 18th power eV). Results of the standard harmonic analysis in right ascension are also presented.
In recent investigations, both theoretical and experimental, the agreement between cascade theory and experimental data is pointed out. The radial distributions obtained from the Monte Carlo simulation are compared ith the results of the analytical theory for all particles in cascades. The data on the mean radius of electron lateral distribution in air are compared with those in lead.
Electron density profiles derived from rocket-borne measurements are presented. These data were obtained at two different sites in northern Scandinavia under various degrees of geophysical disturbance. The observed electron density profiles are related to ionospheric absorption as observed with the dense riometer network in that area.
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Energetic neutral atoms (ENA), emitted from the magnetosphere with energies of about 50 keV, have been measured with solid state detectors on the IMP 7/8 and ISEE 1 spacecraft; they are produced when singly charged trapped ions collide with the exosphere neutral hydrogen geocorona and the energetic ions are neutralized by charge exchange. ENA observations during the recovery phase of two moderate geomagnetic storms are analyzed: November 22-23, 1973, from IMP 8 at 33 earth radii and December 17, 1977, from ISEE 1 at 20 earth radii.