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New line parameters for two heavy odd nitrogen molecules HNO3 in the nu(sub 5)/2nu(sub 9) region, and ClONO2 in the nu(sub 4) region are incorporated in the analysis of high resolution i.r. atmospheric spectra. The line parameters are tested and renormalized vs laboratory spectra, and then applied to retrievals from balloon-borne and ground-based solar absorption spectra.
Superconducting transition comes into being between 92 K and 82 K in the samples having a Meissner's state value of 68 vol. percent. The main material content has an orthorhombic unit cell of Y1Ba2Cu408 accompanied by low quantity CuO and a sporadic phase. A proof of anisotropic superconductivity, an unusually high Cu ion concentration and a temperature dependent transition of charge carriers have been observed.
The relative importance of various odd nitrogen (NOy) sources including lightning, aircraft, and surface emissions on upper tropospheric total odd nitrogen is illustrated as a first application of the three-dimensional Stretched-Grid University of Maryland/Goddard Chemical-Transport Model (SG-GCTM). The SG-GCTM has been developed to look at the effect of localized sources and/or small scale mixing processes on the large-scale or global chemical balance. For this simulation, the stretched-arid was chosen so that its maximum resolution is located over eastern North America and the North Atlantic; a region that includes most of the SONEX (the SASS (Subsonic Assessment) Ozone and Nitrogen Oxides Experiment) flight paths. The SONEX period (October-November 1997) is simulated by driving the SG-GCTM with assimilated data from the GEOS-STRAT DAS (Goddard Earth Observing System-STRAT Data Assimilation System). A new algorithm is used to parameterize the lightning, flash rates that are needed to calculate emissions of NOy by lightning. Model-calculated upper tropospheric NOy and NOy measurements from the NASA DC-8 aircraft are compared. Spatial variations in NOy were well captured especially with the stretched-grid run; however, model-calculated concentrations were often too high in the upper troposphere, particularly during the first several flights. The lightning algorithm does a reasonably good job; however, the use of emissions from observed lightning, flashes significantly improves the simulation on a few occasions, especially November 3, 1997, indicating that significant uncertainty remains in parameterizing lightning in CTMS. Aircraft emissions play a relatively minor role (about 12%) in the upper tropospheric NOY budget averaged along SONEX flight paths; however, the contribution of such emmissions is as large as about 30% during portions of some flights.
Analysis of nitrates measured in polar ice cap snow at a high resolution shows large variations in the nitrates. It has been shown that the nitrate signal may contain a signature of solar activity [Zeller and Dreschhoff, 19951. Reactive odd nitrogen production associated with solar particle events (SPEs) and auroral activity may be a source of some of the nitrate anomalies observed in the polar ice caps. Periods of large SPEs can lead to a production of polar atmospheric odd nitrogen in excess of the ambient sources in the polar stratosphere and mesosphere, and may leave a large nitrate signal stratified in the polar ice cap. Auroral electrons and photoelectrons produce odd nitrogen in the thermosphere, some of which may be transported to the polar (>50 degrees) mesosphere and stratosphere. Sources of odd nitrogen in the polar middle atmosphere associated with SPEs, galactic cosmic rays, and auroral electron precipitation have been quantified. The relative contributions by the energetic particles sources to the Noy budget of the polar middle atmosphere (from tropopause to 50 km, from 50 degrees to 90 degrees latitude) are compared with the nitrates observed in the polar ice sheets.
New line parameters for two heavy odd nitrogen molecules HNO3 in the upsilon(sub 5)/2upsilon(sub 9) region, and ClONO2 in the upsilon(sub 4) region are incorporated in the analysis of high resolution i.r. atmospheric spectra. The line parameters arc tested and renormalized vs laboratory spectra, and then applied to retrievals from balloon-borne and ground-based solar absorption spectra.
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Attitude maneuvers of a spacecraft generate changes int he spacecraft rotatinal state.
The NASA Orbiting Technology Test-bed Inititative (OTTI) will evaluate the effects of real-time space environments on advanced spacecraft technologies.
Volume mixing ratio profiles of the quantitatively significant NOy species NO, NO2, HNO3, HNO4, CINO3 and N2O5 were measured remotely form 8 to 38 km by the JPL MkIV FTIR solar absorption spectrometer during balloon flights from Fairbanks, Alaska on May 8 and July 8, 1997.
During the summer of 2007, as part of the second year of a NASA-funded project in partnership with Christopher Newport University called SPHERE (Students as Professionals Helping Educators Research the Earth), a group of undergraduate students spent 8 weeks in a research internship at or near NASA Langley Research Center. Three students from this group formed the Clouds group along with a NASA mentor (Chambers), and the brief addition of a local high school student fulfilling a mentorship requirement. The Clouds group was given the task of exploring and analyzing ground-based cloud observations obtained by K-12 students as part of the Students' Cloud Observations On-Line (S'COOL) Project, and the corresponding satellite data. This project began in 1997. The primary analysis tools developed for it were in FORTRAN, a computer language none of the students were familiar with. While they persevered through computer challenges and picky syntax, it eventually became obvious that this was not the most fruitful approach for a project aimed at motivating K-12 students to do their own data analysis. Thus, about halfway through the summer the group shifted its focus to more modern data analysis and visualization tools, namely spreadsheets and Google(tm) Earth. The result of their efforts, so far, is two different Excel spreadsheets and a Google(tm) Earth file. The spreadsheets are set up to allow participating classrooms to paste in a particular dataset of interest, using the standard S'COOL format, and easily perform a variety of analyses and comparisons of the ground cloud observation reports and their correspondence with the satellite data. This includes summarizing cloud occurrence and cloud cover statistics, and comparing cloud cover measurements from the two points of view. A visual classification tool is also provided to compare the cloud levels reported from the two viewpoints. This provides a statistical counterpart to the existing S'COOL data visualization tool, which is used for individual ground-to-satellite correspondences. The Google(tm) Earth file contains a set of placemarks and ground overlays to show participating students the area around their school that the satellite is measuring. This approach will be automated and made interactive by the S'COOL database expert and will also be used to help refine the latitude/longitude location of the participating schools. Once complete, these new data analysis tools will be posted on the S'COOL website for use by the project participants in schools around the US and the world.
The item to be cleared is a low-fidelity software simulation model of a hypothetical freeflying robot designed for use in zero gravity environments. This simulation model works with the HCC simulation system that was developed by Xerox PARC and NASA Ames Research Center. HCC has been previously cleared for distribution. When used with the HCC software, the model computes the location and orientation of the simulated robot over time. Failures (such as a broken motor) can be injected into the simulation to produce simulated behavior corresponding to the failure. Release of this simulation will allow researchers to test their software diagnosis systems by attempting to diagnose the simulated failure from the simulated behavior. This model does not contain any encryption software nor can it perform any control tasks that might be export controlled.
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Interpreting the relationship between "enriched" olivine-phyric shergottites (e.g. NWA 1068/1110) and the "enriched" pyroxene-plagioclase shergottites (e.g. Shergotty, Los Angeles) is problematic. Symes et al. [1] and Shearer et al. [2]) proposed that the basaltic magma that crystallized to produce olivine-phyric shergottite NWA 1068/1110 could produce pyroxene-plagioclase shergottites with additional fractional crystallization. However, additional observations indicate that the relationship among the enriched shergottites may be more complex [1-3]. For example, Herd [3] concluded that some portion of the olivine megacrysts in this meteorite was xenocrystic in origin, seemingly derived from more reduced basaltic liquids. This conclusion may imply that a variety of complex processes such as magma mixing, entrainment, and assimilation may play important roles in the petrologic history of these meteorites. It is therefore possible that these processes have obscured the petrogenetic linkages between the enriched olivine-phyric shergottites and the pyroxene-plagioclase shergottites. As a first order step in attempting to unravel these petrologic complexities, this study focuses upon exploring the effect of fO2 on the crystallization history for an analog primitive shergottite liquid composition (Y98). Results from this work will provide a basis for reconstructing the record of fO2 in shergottites, its effect on both mineral chemistries and valence state partitioning, and a means for examining the role of crystallization on the petrologic linkages between olivine-phyric and pyroxene-plagioclase shergottites. A companion abstract [4] explores the behavior of V over this range of fO2.
A spiked (with REE, V, Sc) martian basalt Y980459 composition was used to synthesize olivine, spinel, and pyroxene at 1200 C at 5 oxygen fugacities: IW-1, IW, IW+1, IW+2, and QFM. The high spike levels for REE were used for two specific reasons. First, we wanted to be able to analyze REE by both electron microprobe and ion probe. Second, we wanted the most important "Others" components, (i.e., those outside the pyroxene quadrilateral such as Al, Cr3+, Fe3+, REE3+, V3+, V4+, etc.) to be REE3+Mg (Si,Al)2O6. At the doped levels we used, the most important "Others" component is REE3+ in the M2 site coupled with Al in the tetrahedral site. The goal of this paper is to explain the significant increase in the value of D(sub V)(sup pyroxene/melt) with increased Wo content of the pyroxene. We compare augite (Wo approx. 33), pigeonite (Wo approx. 13) and orthopyroxene (Wo approx 3.8). We also show olivine for comparison. The crystal chemical factors which account for this remarkable increase of DV with Wo are twofold. First, with Ca in the M2 site (as in diopside, CaMgSi2O6) the site is large and 8-coordinated while Mg in the M2 site (as in enstatite, Mg2Si2O6) the site is smaller and 6- coordinated. Second, tetrahedral Al in the pyroxene chains provides charge balance and makes the M2 site larger and more compliant for the introduction of REE.