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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS1998

Spectrum Preprocessing in the OPAD System

To determine the readiness of a rocket engine, and facilitate decisions on continued use of the engine before servicing is required, high-resolution optical spectrometers are used to acquire spectra from the exhaust plume. Such instruments are in place at the Technology Test Bed (TTB) stand at Marshall Space Flight Center (MSFC) and the A1 stand at Stennis Space Center (SSC). The optical spectrometers in place have a wide wavelength range covering the visible and near-infrared regions, taking approximately 8000 measurements at about one Angstrom spacing every half second. In the early stages of this work, data analysis was done manually. A simple spectral model produced a theoretical spectrum for given amount of elements and an operator visually matched the theoretical and real spectra. Currently, extensive software is being developed to receive data from the spectrometer and automatically generate an estimate of element amounts in the plume. It will result in fast and reliable analysis, with the capability of real-time performance. This software is the result of efforts of several groups but mainly it has been developed and used by scientists and combustion engineers, in their effort of understanding the underlying physical processes and phenomena and creating visualization and report generation facilities. Most of the software has been developed using the IDL language and programming environment which allows for extensive data visualization. Although this environment has been very beneficial, the resulting programs execute very slowly and are not easily portable to more popular, real-time environments. The need for portability and high speed of execution is becoming more apparent as the software matures moving out of the experimentation stage and into the production stage where ease of use and short response time are the most desirable features. The purpose of the work described here is to assist the scientists who developed the original IDL-based version in the conversion of the software into the real-time, production version. Specifically, a section of the software devoted to the preprocessing of the spectra has been converted into the C language. In addition, parts of this software which may be improved have been identified, and recommendations are given to improve the functionality and ease of use of the new version.

Katsinis, Constantine↗
NASA NTRS2010

The Radio Jove Project

The Radio love Project is a hands-on education and outreach project in which students, or any other interested individuals or groups build a radio telescope from a kit, operate the radio telescope, transmit the resulting signals through the internet if desired, analyze the results, and share the results with others through archives or general discussions among the observers. Radio love is intended to provide an introduction to radio astronomy for the observer. The equipment allows the user to observe radio signals from Jupiter, the Sun, the galaxy, and Earth-based radiation both natural and man-made. The project was started through a NASA Director's Discretionary Fund grant more than ten years ago. it has continued to be carried out through the dedicated efforts of a group of mainly volunteers. Dearly 1500 kits have been distributed throughout the world. Participation can also be done without building a kit. Pre-built kits are available. Users can also monitor remote radio telescopes through the internet using free downloadable software available through the radiosky.com website. There have been many stories of prize-winning projects, inspirational results, collaborative efforts, etc. We continue to build the community of observers and are always open to new thoughts about how to inspire the observers to still greater involvement in the science and technology associated with Radio Jove.

Thieman, J. R.↗
NASA NTRS2014

Phase Transitions in Planning Problems: Design and Analysis of Parameterized Families of Hard Planning Problems

There are two common ways to evaluate algorithms: performance on benchmark problems derived from real applications and analysis of performance on parametrized families of problems. The two approaches complement each other, each having its advantages and disadvantages. The planning community has concentrated on the first approach, with few ways of generating parametrized families of hard problems known prior to this work. Our group's main interest is in comparing approaches to solving planning problems using a novel type of computational device - a quantum annealer - to existing state-of-the-art planning algorithms. Because only small-scale quantum annealers are available, we must compare on small problem sizes. Small problems are primarily useful for comparison only if they are instances of parametrized families of problems for which scaling analysis can be done. In this technical report, we discuss our approach to the generation of hard planning problems from classes of well-studied NP-complete problems that map naturally to planning problems or to aspects of planning problems that many practical planning problems share. These problem classes exhibit a phase transition between easy-to-solve and easy-to-show-unsolvable planning problems. The parametrized families of hard planning problems lie at the phase transition. The exponential scaling of hardness with problem size is apparent in these families even at very small problem sizes, thus enabling us to characterize even very small problems as hard. The families we developed will prove generally useful to the planning community in analyzing the performance of planning algorithms, providing a complementary approach to existing evaluation methods. We illustrate the hardness of these problems and their scaling with results on four state-of-the-art planners, observing significant differences between these planners on these problem families. Finally, we describe two general, and quite different, mappings of planning problems to QUBOs, the form of input required for a quantum annealing machine such as the D-Wave II.

Problems↗
NASA NTRS2018

Developing a Remotely Sensed Drought Monitoring Indicator for Morocco

Drought is one of the most serious climatic and natural disasters inflicting serious impacts on the socio-economy of Morocco, which is characterized both by low-average annual rainfall and high irregularity in the spatial distribution and timing of precipitation across the country. This work aims to develop a comprehensive and integrated method for drought monitoring based on remote sensing techniques. The main input parameters are derived monthly from satellite data at the national scale and are then combined to generate a composite drought index presenting different severity classes of drought. The input parameters are: Standardized Precipitation Index calculated from satellite-based precipitation data since 1981 (CHIRPS), anomalies in the day-night difference of Land Surface Temperature as a proxy for soil moisture, Normalized Difference Vegetation Index anomalies from Moderate Resolution Imaging Spectroradiometer (MODIS) data and Evapotranspiration anomalies from surface energy balance modeling. All of these satellite-based indices are being used to monitor vegetation condition, rainfall and land surface temperature. The weighted combination of these input parameters into one composite indicator takes into account the importance of the rainfall-based parameter (SPI). The composite drought index maps were generated during the growing seasons going back to 2003. These maps have been compared to both the historical, in situ precipitation data across Morocco and with the historical yield data across different provinces with information being available since 2000. The maps are disseminated monthly to several main stakeholders' groups including the Ministry of Agriculture and Department of Water in Morocco.

Drought monitoring↗
NASA NTRSDate not supplied

Solar Energetic Particle Tracks in Itokawa Samples: Implications for Regolith Development on Near-Earth Asteroids and Space Weathering

JAXA’s Hayabusa mission returned the first surface samples from a near-Earth asteroid for laboratory analyses. The Hayabusa samples thus provide a special opportunity to directly investigate the evolution of asteroidal surfaces, from the development and evolution of the regolith to the study of space weathering effects. The lack of a protective atmosphere on airless bodies results in regolith grains being exposed to a wide range of radiation sources and effects. We focus here on solar energetic particles (SEP) with Z>20, mainly Fe group nuclei, that leave trails of ionization damage (tracks) in insulating materials that accumulate with time and provide clues about the near-surface exposure age of regolith materials.

L P Keller↗
NASA NTRSDate not supplied

Determining Surface Exposure Ages of Regolith Grains in Lunar Core Sample 73002 By Investigating Solar Particle Irradiation Damage

Space weathering causes the surface soils of airless bodies like the Moon to be micro-structurally and chemically altered by exposure to micrometeoroid bombardment and solar wind irradiation. These alterations accumulate in surface grains with continued residence in the uppermost millimeters of regolith. Low energy solar wind ions (largely H+ and He+) produce a layer of radiation damage as they become implanted in grain surfaces. Also present are solar energetic particle (SEP) tracks, which are nanoscale lineations within grain interiors formed by heavy, high-energy ions (mainly Fe group nuclei) penetrating up to millimeters below the surface. Recent work has determined that the width of solar wind-damaged rims on anorthite and olivine, and their respective SEP track densities are correlated with each other and with grain surface exposure age. Core sample 73002, recently released under the Apollo Next Generation Sample Analysis (ANGSA) Program, has provided an opportunity to study material collected from the light mantle formation in the Taurus-Littrow Valley during Apollo 17. The light mantle is thought to have been deposited vial and slide originating from the neighboring South Massif. Spectral analysis of bulk core soils found a plagioclase rich composition, confirming a highlands origin of the formation. Spectral profiles and ferromagnetic resonance (FMR) measurements of bulk soils sampled at cm-intervals from 73002 indicate that regolith up to~9.5 cm in depth have maturity indices consistent with longer durations of surface processing than samples deeper in the core. Thus, this upper ~9 cm layer likely represents the maximum extent of an in-situ reworking zone which may have persisted over 5 to 17million years. Here we present an analysis of grain exposure ages within the in-situ reworking zone of 73002derived from SEP track density measurements via transmission electron microscopy.

J A McFadden↗
NASA NTRSDate not supplied

High Reynolds Number Testing of the NATO AVT-298 SWiFT Configuration at the National Transonic Facility

A high Reynolds number wind tunnel test of the NATO AVT-298 Swept Wing Flow Test (SWiFT) configuration was conducted in the National Transonic Facility at the NASA Langley Research Center during the summer of 2023. The SWiFT research model geometry has relevance to both blended/hybrid wing body (BWB/HWB) and unmanned combat aerial vehicle (UCAV) configurations, and the test campaign was the culmination of an international collaboration under the NATO AVT-298 research task group. The main objectives of the test were to investigate Reynolds number scaling effects on low-speed stability & control characteristics and to examine the onset and progression of flow separation on the wings particularly near the wing crank. Force & moment and surface pressure data were acquired at Mach numbers from 0.2 to 0.8, Reynolds numbers from 2.5 to 34 million, angles of attack from -3 to 20 degrees, and sideslip angles from -10 to 10 degrees. Boundary layer transition detection techniques utilizing static pressure taps, unsteady pressure transducers, and sublimating chemicals were used on the model in a free/natural transition state or a forced transition state using trip dots. Pressure sensitive paint was used to obtain a global surface pressure profile on the model and an advanced laser velocimetry technique was used to obtain velocity measurements in the wake downstream of the wing crank. The results from the test showed clear Reynolds number scaling effects on the maximum lift coefficient and pitching moment coefficient at Mach 0.2, while also capturing significant hysteresis effects. The data acquired from the test will ultimately help improve computational aerodynamic analysis and design tools for application to future BWB-type vehicle configurations.

NATO AVT-298↗
NASA NTRSDate not supplied

Surface Pressure Results for the NATO AVT-298 SWiFT Configuration in the National Transonic Facility

A high Reynolds number wind tunnel test of the Swept Wing Flow Test (SWiFT) configuration was conducted in the National Transonic Facility at the NASA Langley Research Center during the summer of 2023. The test campaign was the culmination of an international collaboration under the NATO AVT-298 research task group. The main objective of the test was to investigate Reynolds number scaling effects on the low-speed stability & control characteristics of the SWiFT model. Surface pressure results corroborate the force & moment results and help to provide more insight into the observed flow behavior. The effect of angle of attack and Reynolds number on the low-speed surface pressure results are analyzed particularly around the leading edge of the model. The onset and progression of flow separation on the wings particularly near the wing crank is also investigated, as well as the cause of an observed double-stall behavior. Finally, the transonic results showed a slight forward movement of the shock location with decreased shock strength as Reynolds number was increased. The data acquired from the test will ultimately help improve computational aerodynamic analysis and design tools for application to future BWB-type vehicle configurations.

NATO AVT-298↗
NASA NTRS2025

Large Impact Features on Ganymede and Callisto as Revealed By Geological Mapping and Morphometry

The icy Galilean satellites are host to a broad range of impact feature morphologies. Hypotheses seeking to explain the diversity of these impact features consider the effects of impact melt, the physical state of the subsurface at the time of impact, and the impactor characteristics. As part of a larger effort to assess the role of these factors in the formation and evolution of these impact features, we have performed topographic and geological mapping of 19 large impact features on Ganymede and Callisto. These are divided into two main morphological groups: craters (subdivided into pit, dome, and anomalous dome craters), and penepalimpsests/palimpsests. The transitions from pit, dome, to anomalous dome craters appear to be size-dependent up to diameters of ∼170 km. The morphologies of pit and dome craters appear to be independent of their age or geologic context. The impacts that formed them only affected a cold, rigid ice layer, with the development of pits and raised annuli on their floors possibly stemming from the evolution of a pocket of impact melt. The subdued rims and floors of anomalous dome craters indicate the increasing effect of a weak, warm ice layer on impact feature morphology with increasing size, but their prominent annuli and pits indicate that mobilization of impact melt is also a factor. The very low topographic relief of older penepalimpsests and palimpsests indicates that their impacts penetrated the ice shell to mobilize very large volumes of pre-existing liquid from a subsurface layer, with little contribution to the final feature morphology from impact melt. Penepalimpsests are distinguished from palimpsests by the higher frequency of concentric ridges within their interiors, indicating a generally more robust state of the subsurface that could better support the rotation and uplift of solid material during impact, even if a crater-like depression could not be supported. A few impact features seem to be transitional between anomalous dome craters and penepalimpsests, and the overlap of anomalous dome craters, penepalimpsests, and palimpsests in terms of diameter as well as age indicates that impactor size and subsurface properties over time are major factors in determining which of these morphologies emerges.

Oliver L White↗
NASA NTRSDate not supplied

High Reynolds Number Testing of the NATO AVT-298 SWiFT Configuration at the National Transonic Facility

A high Reynolds number wind tunnel test of the NATO AVT-298 Swept Wing Flow Test (SWiFT) configuration was conducted in the National Transonic Facility at the NASA Langley Research Center during the summer of 2023. The SWiFT research model geometry has relevance to both blended/hybrid wing body (BWB/HWB) and unmanned combat aerial vehicle (UCAV) configurations, and the test campaign was the culmination of an international collaboration under the NATO AVT-298 research task group. The main objectives of the test were to investigate Reynolds number scaling effects on low-speed stability & control characteristics and to examine the onset and progression of flow separation on the wings particularly near the wing crank. Force & moment and surface pressure data were acquired at Mach numbers from 0.2 to 0.8, Reynolds numbers from 2.5 to 34 million, angles of attack from -3 to 20 degrees, and sideslip angles from -10 to 10 degrees. Boundary layer transition detection techniques utilizing static pressure taps, unsteady pressure transducers, and sublimating chemicals were used on the model in a free/natural transition state or a forced transition state using trip dots. Pressure sensitive paint was used to obtain a global surface pressure profile on the model and an advanced laser velocimetry technique was used to obtain velocity measurements in the wake downstream of the wing crank. The results from the test showed clear Reynolds number scaling effects on the maximum lift coefficient and pitching moment coefficient at Mach 0.2, while also capturing significant hysteresis effects. The data acquired from the test will ultimately help improve computational aerodynamic analysis and design tools for application to future BWB-type vehicle configurations.

BWB/HWB↗
NASA NTRSDate not supplied

Surface Pressure Results for the NATO AVT-298 SWiFT Configuration in the National Transonic Facility

A high Reynolds number wind tunnel test of the Swept Wing Flow Test (SWiFT) configuration was conducted in the National Transonic Facility at the NASA Langley Research Center during the summer of 2023. The test campaign was the culmination of an international collaboration under the NATO AVT-298 research task group. The main objective of the test was to investigate Reynolds number scaling effects on the low-speed stability & control characteristics of the SWiFT model. Surface pressure results corroborate the force & moment results and help to provide more insight into the observed flow behavior. The effect of angle of attack and Reynolds number on the low-speed surface pressure results are analyzed particularly around the leading edge of the model. The onset and progression of flow separation on the wings particularly near the wing crank is also investigated, as well as the cause of an observed double-stall behavior. Finally, the transonic results showed a slight forward movement of the shock location with decreased shock strength as Reynolds number was increased. The data acquired from the test will ultimately help improve computational aerodynamic analysis and design tools for application to future BWB-type vehicle configurations.

NATO AVT-298↗
DOE OSTI2022

Aromatic surfactants

Disclosed are compounds of the Formula 1 wherein A is an aromatic moiety; H is a hydrophobic group comprising a main alkyl chain having from about 3 to about 26 carbon atoms and comprising a C 2 or greater alkyl chain branched from the main alkyl chain; and K is a hydrophilic group.

Krumm, Christoph↗
NASA NTRS2002

Cosmochemical Studies: Meteorites, Asteroidal Processes, Chondrules

Our research mainly concerned the asteroidal processes involved in the formation of meteorites and meteoritic chondrules. We continued to generate large amounts of instrumental-neutron-activation analysis (INAA) data, both for irons, chondrites and primitive achondrites. Major themes of our chondrule research were: (1) the temperature and crystallization history of individual chondrules, and (2) the evolution of the solar nebula during the period within which chondrule formation occurred. Much of our chondrule research was focused on the highly primitive CO3 chondrites. We initiated a study of the cooling history of high-FeO chondrules by characterizing the overgrowth layers on relict grains.. We also continued our studies of the composition and the formation of iron meteorites and the evolution of their parent planets. The large data sets that we have generated at UCLA allows systematic comparisons of the large magmatic groups both in terms of fractional crystallization (including rough estimates of non-metal contents of the parental melts) and in terms of the effects of variable contents of trapped melt. We have completed a preliminary study of group IIIAB in which we developed a trapped-melt model and more detailed studies of group IVA and the main-group pallasites. By comparing these large groups and modeling them by a combination of crystallization and melt trapping, we are able to better define both the formation processes and the nature of the solid/liquid elemental partitioning. We helped maintain the excellent neutron-activation facilities at UCLA, a major resource for the cosmochemical community.

Wasson, John T.↗
DOE OSTI2023

The influence of submarine canyons-related processes on recent benthic foraminiferal distribution, Espírito Santo Basin, Southeastern Brazil

The complex topography of submarine canyons may result in different composition of benthic foraminifera assemblages. To understand how trophic, hydrological and sedimentological conditions in submarine canyons can influence the distribution of benthic foraminifera, and to use this information to corroborate paleoenvironmental interpretations for the Holocene, we investigated recent benthic foraminiferal assemblages (total fauna >63 μm) and sedimentological data in two canyons (CANWN and CAND) in the Espírito Santo Basin (ESB) between 18°20' and 21°20' S. Surface sediment samples (0–2 cm) were collected inside the canyons (150 to 1300 m water depth) and in shelf-slope adjacent transects (50 to 1300 m water depth). The density, taxonomic diversity, and assemblage composition of benthic foraminifera change with depth and location. The distinct ecological preferences of the most abundant taxa allowed us to recognize five benthic foraminiferal groups. Three groups (V, III, and I) are present in different bathymetric sectors; Group V: outer shelf (50 m), Group III: upper, and middle – lower slope (150 to 400 m), and Group I: middle – lower slope (1000 to 1300 m). Groups II and IV show no characteristic bathymetric distribution and are present only in CAND and in CANWN, respectively. Group V consists of Hanzawaia boueana, Peneroplis planatus, and Quinqueloculina lamarckiana; Group III is dominated by Globocassidulina rossensis and Trifarina spp.; Group I consists of Globocassidulina crassa, Bolivina lowmani, Gavelinopsis versiformis, Alabaminella weddellensis, and Epistominella exigua. The main species in Group II (CAND, 150, 1000 to 1300 m) are Trifarina angulosa, Globocassidulina subglobosa, and Discorbis vilardeboanus. Group IV (middle – lower CANWN, 1000 to 1300 m), consists mainly of agglutinated species Glomospira charoides, Rhabdammina abyssorum, and Psammosphaera fusca. Further, our data suggest that the quantity (and quality) of food supply, hydrodynamic conditions and sediment properties are the main drivers controlling the bathymetric distribution of benthic foraminiferal assemblages in both canyons. The middle – lower CANNW revealed unstable trophic conditions, related to terrigenous sediment input due to turbidity currents. In CAND, the foraminiferal assemblages ecology indicated sufficient organic matter supply that favors species establishment and diversity, indicating a more productive and less unstable environment than in CANWN.

58 GEOSCIENCES↗
DOE OSTI2021

Recurrent Activity from Active Asteroid (248370) 2005 QN 173 : A Main-belt Comet

We present archival observations of main-belt asteroid (248370) 2005 QN 173 (also designated 433P) that demonstrate this recently discovered active asteroid (a body with a dynamically asteroidal orbit displaying a tail or coma) has had at least one additional apparition of activity near perihelion during a prior orbit. We discovered evidence of this second activity epoch in an image captured 2016 July 22 with the DECam on the 4 m Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile. As of this writing, (248370) 2005 QN 173 is just the eighth active asteroid demonstrated to undergo recurrent activity near perihelion. Our analyses demonstrate (248370) 2005 QN 173 is likely a member of the active asteroid subset known as main-belt comets, a group of objects that orbit in the main asteroid belt that exhibit activity that is specifically driven by sublimation. We implement an activity detection technique, wedge photometry, that has the potential to detect tails in images of solar system objects and quantify their agreement with computed antisolar and antimotion vectors normally associated with observed tail directions. We present a catalog and an image gallery of archival observations. The object will soon become unobservable as it passes behind the Sun as seen from Earth, and when it again becomes visible (late 2022) it will be farther than 3 au from the Sun. Our findings suggest (248370) 2005 QN 173 is most active interior to 2.7 au (0.3 au from perihelion), so we encourage the community to observe and study this special object before 2021 December.

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS1995

Final Report of the IAG AD Hoc Working Group on Global Change

None given. Paper gives final report of the IAG ad hoc working group on global change. They made three main recommendations to the group: 1. the post of and IAG liaison or representative to the IGBP should be established. 2. A new core program,.

IAG global change IGBP International Geosphere-Bio↗
DOE OSTI2023

Effects of submerged macrophytes (Elodea nuttallii) on water quality and microbial communities of largemouth bass (Micropterus salmoides) ponds

Traditional aquaculture ponds are one of the most vulnerable ecosystems; thus, ecological aquaculture is increasingly valued for its beneficial ecological properties and ecosystem services. However, little is known about ecological aquaculture of largemouth bass with submerged vegetation. Here, we designed three ecological ponds of cultured largemouth bass with submerged macrophytes (the EM group) and three ponds with traditional aquaculture (the M group) to reveal the response of water quality, and phytoplankton and bacterial communities, to submerged macrophyte bioremediation during a 90-day culture period. We observed that Cyanobacterial outbreak occurred in the M group ponds from day 7 to the end of the experiment; however, there were no Cyanobacterial blooms in the EM group ponds throughout the culture period. Compared with the M group ponds, the EM group ponds, which had submerged hydrophytes, had significantly decreased concentrations of TP, TN, and COD Mn , but significantly increased DO concentrations throughout the experimental period. Moreover, ecological aquaculture with submerged macrophytes showed strong effects on the phytoplankton and bacterial community compositions. In particular, the M group ponds had higher phytoplankton density and mainly included Cyanobacteria, whereas the EM group had lower phytoplankton density and mainly included Chlorophyta. Moreover, higher alpha diversity, as determined by Ace and Simpson index values, was detected for bacterial communities in the EM group ponds. Furthermore, PCoA clearly grouped the bacterial communities according to the two culture modes throughout the culture period. These results indicate that ecological aquaculture with submerged macrophytes can improve water quality, control Cyanobacterial blooms, and affect the diversity and composition of bacterial communities. These valuable effects seem to be beneficial and consistent to maintaining aquaculture ecosystem stability.

Nie, Zhijuan↗
DOE OSTI2021

Latin American Strategy for Research Infrastructures for High Energy, Cosmology, Astroparticle Physics LASF4RI for HECAP

The present document, the Latin American HECAP Physics Briefing Book, is the result of this ambitious grass roots effort. This report contains the work performed by the Preparatory Group to synthesize the main contributions and discussions for each of the topical working groups: Astronomy, Astrophysics and Astroparticle Physics; Cosmology; Dark Matter; Neutrinos; Electroweak and Strong Interactions, Higgs physics, Flavour and CP Physics and Beyond the Standard Model Physics; Instrumentation and Computing. This work aims at providing a landscape of existing expertise and capabilities. It will hopefully instruct some recommendations for further development of strategic research infrastructures relevant for future HECAP efforts in the region as well as for a continuous and successful involvement of Latin American HECAP researchers in the global arena.

43 PARTICLE ACCELERATORS↗